Idk why my game cuts off from all side by a bit when im in windowed mode. So i have to play fullscreen. But i cant see the timer in fullscreen mode and i dont have a second monitor. Am I allowed to use windowed fullscreen? Alternatively, can someone tell me the solution to the issue? I wish i could add an image to show you what my game looks like.

i can safely assume: yes.
but you should ask game specific questions in the game specific forums

What SioN said, but yeah I don't see how that would matter at all.

Recording software like OBS can record just fine with windowed or fullscreen or windowed fullscreen without issues.

Have you checked the size that your obs records? You can always try another screen recorder like bandicam.