What do you mean by "believing in yourself"? I'm pretty sure I exist, indeed it would be a logical conundrum to think otherwise. Belief doesn't figure here.
What else should I believe in?
I don't believe that gravity is real, I just operate my life on the assumption that it exists and is predictable. It's working great so far.
I don't believe climate change is real, but I accept the evidence provided, and will continue to do so until such time as I'm provided with further evidence to consider.
I don't believe my mother loves me, I'm quite satisfied that she does. I have enough evidence.
Ah, so you define the word "to believe" as "to have blind faith in", rather than "to estimate a very large probability with high confidence that a proposition is true."
What else should I believe in?
I don't believe that gravity is real, I just operate my life on the assumption that it exists and is predictable. It's working great so far.
I don't believe climate change is real, but I accept the evidence provided, and will continue to do so until such time as I'm provided with further evidence to consider.
I don't believe my mother loves me, I'm quite satisfied that she does. I have enough evidence.