My favorite programs for Windows
These are apps that you should start using, everything here is open source unless marked otherwise.
You should use this instead of VLC Media Player, it's pretty much VLC but way better in alot of ways, it has a minimalistic look, you can customize it with custom OSCs, (also doesn't look like an ancient media player) and you can improve it even further by creating a config file, you can learn more about this by following iamascum's guides. If you feel like it's too hard to use, you should try mpv.net, fork of MPV that is more user friendly.
Screen mirroring tool, much better than something like ApowerMirror
Useful tool to download multiple files from Mega easily, no limits on how much you can download.
Package manager, somewhat like Linux's package managers, if you want an alternative not tied to NuGet, you should try scoop, however scoop has a smaller amount of packages compared to Chocolatey.
Open source alternative to CCleaner, I wouldn't trust CCleaner so I recommend using this instead.
Python IDE, there's an open source and a closed source version.
Open source fork of Visual Studio Code, pretty much the same but with removed telemetry.
Alternative to Windows's File Explorer. Supports tabs and custom themes and overall feels much smoother than the normal File Explorer.
Closed source, however it's very useful when searching for a specific file, much better experience than searching for it in File Explorer.
Minimalistic open source PDF Reader.
Useful comic reader, if you do not like this, try CDisplay Ex.
I love this app, it allows you to create webapps.
Open source alternative to Photos.