I'm not saying you shouldn't force yourself out of your comfort zone, but perhaps you could try this: Find a fun problem and solve it with the new tech/language

I'm not saying you shouldn't force yourself out of your comfort zone, but perhaps you could try this: Find a fun problem and solve it with the new tech/language you are trying to learn. It a lot easier when "fun" drives your efforts instead of forcing yourself to do something. As for feeling dumb when learning new things; you may have to accept that no amount of experience/data point will let you "prove to yourself" that you will be good at a new challenge. My software engineer/wife/best friend pretty much rocks at every job she's worked at. I've lost track of how many times she's told me "I don't know if I can do this job." when she starts a new job. She's been going through this cycle of new job=>self doubt=>mastery multiple times for over 2 decades and she still feels that way. Apparently, no amount of data points will dispel that feeling for some people.