Frank did an excellent job in giving you a clear understanding of the use of
mistake!!
As for "kind of" the closest thing to it is "sort of". Both are frequently shortened in speech and come out "kinda" and "sorta". I "kinda" feel like eating ice cream. I feel "sorta" bad. (by the way, that's bad Engilish but you will hear those words very often)
This is just a suggestion but I think these are words that you might want to avoid using until you have become much more familiar with English.
Saludos!