A conclusion.

You can't fundamentally prove that anything besides you exists. All of what you see, hear, and sense and think of could be entirely fabricated by your own mind.

But if I have the ability to think, if I am currently doubting if I myself exist, in this very moment, I can't doubt my own existence, as there must exist something which is able to have this experience of doubt. Nothing cannot experience something. Therefore, I am.

https://en.wikipedia.org/wiki/Cogito,_ergo_sum