HATRED

Audacity - Basic audio recording/manipulation/analysis software. Regularly receives updates even today and has alot of effects.

OBS - Digital recording/streaming software. It's more versatile than people think!! The 'video buffer' feature basically replaces sketchy services like Medal or Overwolf (<- evil) for clipping.

Davinci Resolve - Video editing software. The details page on the website for download may scare people off, but none of it is actually mandatory, you can put anything in and it'll let you get it. Very useful, and has a paid version for some extra fancy effects.

Blender - 2D + 3D Animation/Modelling/VFX software. Complicated, but extremely versatile when learnt. It is worth it to atleast know how to use it for one thing. I personally only know how to animate in it, yet it's still made my life so much easier.

Firealpaca - Art/Image editing software. Yes, there are more professional art programs out there, but I think Firealpaca has the best of both worlds. It has filters/effects I see other programs ask you to pay for while keeping alot of the functionality and basics. Has a paid version (Firealpaca SE) on Steam for some extra things.

Wallpaper Engine - Allows for custom animated wallpapers. This is the only paid one mentioned in this list, but I see so many people using sketchy fake wallpaper programs that I have to atleast mention it. This also allows for wallpapers to be interactable, audio responsive, etc.