who died and made me the DM?

Please note, the following points are all generalisations and the real world is rarely this simple. This is to demonstrate how to use disability aids to contribute to your character's design, not how to make assumptions about real people in real life.

So here are some similarities between the chairs:

Both wheelchairs have ridged frames, this means the wheelchair can't be folded in any way. These kinds of chairs can imply a few different things depending on the person. They are typically lighter, sturdier and more durable, and indicate the person probably will be using the wheelchair for a long time and/or has the money to get something built to last (or lives in a place where cost not an issue due to universal/subsidised access to healthcare). They are also typically better to travel with when flying, as they are less likely to be broken by airport security/staff.

Both wheelchairs also lack anti-tip wheels, which are a third set of wheels that extend from the back of the chair. Them not being present could indicate the person is likely pretty confident in their ability to use the chair without worrying about tipping out. It could also indicate they are in an environment where the anti-tips could be more of a hazard than a help, such as on rough terrain.

So lets look at some specifics for the green wheelchair:

Take a look at the wheels. The front wheels are pretty small and appear to be solid, while the back wheels appear to be quite narrow (compared to the orange chair anyway). This indicates the user likely lives somewhere with decent accessibility like a (well funded) city where they are unlikely to encounter unpaved/dirt roads/grass. Small front wheels and thin back wheels are good for manoeuvrability and a smooth ride over even terrain, but they will get stuck as soon as bumps appear, so this probably isn't an issue for this person.

While its a bit hard to tell unless you have seen other similar wheelchairs, this wheelchair is very long in the front, meaning the footplate and front wheels are further away from the seat than most. There could be a few reasons for this. One either indicates the person has very long legs, or a lack of motion in their knees, making it harder to bend their legs. This is moves the chair's centre of gravity forward by a decent amount, making it harder to tip back, which could indicate the person's legs are very light. You tend to see this most often in the wheelchairs of bilateral leg amputees, who are at a greater risk of tipping backwards due to a lack of weight at the front of the chair (even if they wear their prosthetics).

The colour of the chair is bright. This could simply be the character's favourite colour, or maybe this colour has some significance to them?

There are stickers on the side of the chair relating to the Paralympics. This could indicate the person is a fan, or perhaps had some involvement in the games?

The wheelchair has handles on the back, but they are able to be folded down. This is a popular feature for people who are independent enough to go out on their own, but still want to have the option for some help. folding down the handles also deters random strangers from grabbing at you (an unfortunately common experience for wheelchair users).

There is some mild paint scratching to the front of the wheelchair, but nothing too noticable. This is typical of older chairs and people who are a little rough on their chairs. Maybe they've had a few stacks and falls throughout the years, probably going a decent speed.

Ok, now let's look at the orange chair

This wheelchair has very large, inflatable front wheels, and very thick back wheels. This will make the chair slower and less manoeuvrable on flat/even surfaces, but much, much easier to push on rough terrain. This is supported by the amount of mud on the wheelchair.

The seat on this wheelchair tilts upwards slightly. This is called a bucket (or according to an old basketball teammate of mine, a dump-truck lol). This is a feature you typically see in wheelchairs made for people with spinal injuries who are unable to move their legs and engage their lower bodies or core to help keep them stable.

The back of this chair is very low, indicating that if this wheelchair user has a spinal injury, it's probably pretty low on their spine, likely fairly close to the hips, making the person a low-level paraplegic. Higher-level paraplegics and quadriplegics usually need a higher back to help support them and keep them from flopping over, since all the muscles below their place where their spine broke either doesn't work, or is significantly weaker. Higher backs though can get in the way of pushing and reduce mobility, so people who need less support will likely opt for a lower back rest.

This wheelchair has no handles, which indicates the user is probably very independent and doesn't need a lot of help getting around.

The paint on this wheelchair is very scratched up, showing the person is very tough on their wheelchair and doesn't care to get the paint touched up.

And here are the characters who own these wheelchairs

The owner of the green wheelchair is an amalgamation of a few people I knew from when I played wheelchair basketball. They're a bilateral leg amputee, and judging by their outfit (The Official National Wheelchair Basketball uniform for Australia), they're an elite athlete. This wheelchair is not the one they play sport in, but it still needs to be durable enough to withstand the rough treatment of airport staff when traveling, as well as heavy day-to-day use that comes with being an active person. While it needs to be rough, the person also seemed to want to prioritise speed and manoeuvrability, and likely doesn't need to worry about rough terrain too much, so they probably live in a major city.

The owner of the orange chair was inspired by a family friend of mine. They live on a farm, and need a chair that can handle life in those conditions, rough terrain and all. This comes at the cost of speed and manoeuvrability on smoother terrain, but honestly, anyone who's lived in the country knows you won't find many of those around there anyway, so that's not too big of a sacrifice. They are paraplegic, are very confident in their ability to use their wheelchair, and probably doesn't need help too often, but still benefit from some extra stability support from the raised seat on their chair.

Conclusion

Once again, these are generalisations, and in real life there are always exceptions, but I hope this helped demonstrate what I meant when I said you can use your character's wheelchair to tell us more info about them if you're smart about it.