Hi I have a small question, is it okay if I barely or even don't want to pray at all? Because to me personally it doesn't make that much sense to pray as a sign of worship when I could do devotional acts or give offerings instead, especially when those things feel more personal(?, that isn't exactly the correct word but I can't think of the correct word right now), I'm sorry if this is rude or anything like that!
First, let's take a look at antiquity and start with piety.
Historically, I'd say that when it comes to Hellenic Polytheism, piety could be summed up as 'religiously correct behaviour'.
approaching the gods while wahsed - washing your hands (and sometimes face) with water (especially from a running source; even a tap would be good)
pouring libations to the gods
caring for your shines - cleaning them
Prayer was significant to the Ancient Greek religion and had an important role in the customary worship of the Ancient Greeks.
Saying prayers could look fairly different and their formulas might also somewhat vary, just as the reason behind the prayer can also vary. There are countless examples of this in ancient texts - for example, one might pray to a certain god for a favour (e.g. Chryses - Iliad, 1.35-40) and another might pray for any other reason they may consider important to them. Hell, people even prayed to sort of 'make complaints' to the gods (e.g. Menealos - Iliad, 13.631).
I made a post (LINK) with some basic things about prayer where you can find one of the most common formulas (the 'favor'), but it's certainly not the only way to pray and not he only correct way to do it.
Prayer can very be simple, for example, when pouring libation, the prayer could be something as brief as "I pour this libation of wine (or smth else/wineless libation) for the deathless gods. Receive it kindly."
I've seen a few different ways scholars define prayer in the Ancient Greek religion but, basically a prayer is any act performed in religious context/setting where a person addresses a god.
Now, onto my own thoughts on the matter.
Prayer is important to me personally, since I try to be somewhat historically accurate in my practice, however I can't say I pray every day or that my prayers are always very solemn, lengthy and full of pretty mythological references and plenty of epithets! I don't always have time and energy for something like that, so I might just say any simple prayer I feel the need to say. I engage in devotional acts, too; in some cases also when I might not be able pray that day as some other way to honour the gods.
If for some particular reason someone can't pray, I wouldn't personally consider it an 'offence', especially if they venerate the gods in other ways. Perhaps not including the element of prayer in one's worship just might not be 100% historically accurate but your practice does not need to be 100% historically accurate and to be frank, we can't be fully historically accurate since when it comes to this religion, some things just aren't applicable nowadays, it might be impossible to fully reconstruct them or some things just might still be unknown to us, but that's besides the point. It's important to observe the history and the ancient traditions and to learn about the historical and cultural background of this religion, however ultimately it's up to you to decide what your practice will look like and whether or not you'd like to reconstruct certain things.
To conclude, prayer has been historically important for the worship of Theoi but if you don't focus on historical accuracy in your worship too much, can't/don't want to pray no god will be mad with you. If you do decide to incorporate prayer into your practice and perhaps pray once in a while, you can still make it super simple. But it's awesome if you still do other things to honour the gods and it's fine if those things feel more personal to you.