I felt the same way when switching from a company I liked and spent almost 8 years at to someplace totally new, in a brand new discipline that I was really exci

I felt the same way when switching from a company I liked and spent almost 8 years at to someplace totally new, in a brand new discipline that I was really excited about but didn't have much hands on experience in. It was very anxiety-inducing, since the pandemic really unfolded during my 3-month notice period and here I was leaving a stable position for a brand new probation period. To be honest for me the only thing that solved that clueless feeling was time, and that included overtime. Nobody was forcing me to work extra hours, but I really wanted to prove myself and get up to speed as fast as I could, so I would work late almost every day to become productive asap. Eventually I relaxed more and more, took more and more ownership over various services, developed and released new projects, etc. Before I knew it I had people asking me questions about different services we maintained and different parts of our stack. There were no tricks or strategies that made me feel better other than this type of "brute forcing" it by just powering through. The switch ended up being a good decision, even though I still think fondly of the company I left. Good luck!