A great way to learn is... to learn from your mistakes! Mistakes are not something to be afraid of, or ashamed of. Rather, they are an excellent opportunity to improve! Mistakes are also important when we write proofs, you can read more about this here.
We often think that to be a mathematician we are supposed to be a genius (hence not make mistakes), but that couldn't be further from the truth! Have a look at this video of a discussion between students and faculty about our favourite mistakes to find out more about the issue, including pre and postcognition, the impostor syndrome, the prodigy myth, defining variables to be themselves, being a human in math, and other interesting stuff!
The importance of mistakes is related to the concept of having a growth mindset: this means challenging yourself, trying difficult things, being ok with making mistakes, and using mistakes as an opportunity for growth. To learn more, see this Conversation with Edward B. Burger about The 5 Elements of Effective Thinking (especially on the power of failing) and this Michael Jordan "failure" commercial.
Finally, many of us often wonder if we are good enough to go into math, if we are cut out for it, etc - you can find some answers to this question here.
If you are an instructor and would like to see an activity related to mistakes that I use in some of my courses, let me know!