breathe....
aren't you qualified for this new job?
you can do it, you're just scared about not being able to do it..?

do you do breathing exercises..?
3 Deep Breathing Exercises to Reduce Anxiety | World of Psychology

need to try to calm yourself so that you can function on higher level... more calm you are more you feel you can do...? (within reasonable limits of course...)
maybe think about the reason you are taking the new job...
think about all of the positive things about this for like 5 minutes...
and if you need think about the negative ... but don't over do the negative...
reinforce it with the positive aspects...?

maybe some of this article can help... ?
13 Incredibly Simple Ways to Overcome the Fear of Failure
i cant watch the videos because my data is over limits...

believe in yourself...