At one point everyone was a beginner, even the best of the best. There was a time when it was the very first time a professional did something.
No one was born knowing how to tie their shoes. Things that were once difficult become second nature with repetition and knowledge.
NEVER be afraid to try. NEVER to be afraid to fail, failing is how we learn to succeed.
The ONLY mistake a beginner can make is to not seek knowledge from as many places as they can. Learn as much as you can, compare conflicting opinions, just learn!
Take archery for example, there is a ton of information that goes into becoming an archer, it is overwhelming! Don't be intimidated by those who can shoot bullseyes, they too had to practice and learn. The only thing preventing you from becoming the best you can be is time, practice, and knowledge. Listen to others but don't let them think for you.
Go on any online forum and there will be plenty of arguments for and against techniques, brands, and everything else.
Ignore those that try to intimidate or belittle because you don't know something, once upon a time they didn't know either. Don't be afraid to learn and don't be afraid to be corrected if someone is being genuinely helpful.
TRY. FAIL. LEARN. REPEAT.