This book is a good resource: https://www.amazon.com/Fundamentals-Smart-Contract-Security-Richard/dp/194944936X
Check out the Smart Contract Security Verification Standard too and generally make sure your web2 security knowledge is solid (owasp familiarity, pentesterlab, hackthebox).
SecureFlag also some good Solidity content, ethernauts is also good.
Do you have security experience? It sounds like you don’t so going for a job where you need to pen test and audit contracts sounds like a very quick way to be out of depth. If this is in the case and the company sees through you, it’s quite concerning IMO.
This isn’t to say you can’t get into the field, but you can’t just learn this stuff over night and if it’s for a junior position and they see your passion and willingness to learn, great, but don’t pretend to know how to audit if you don’t. I can suggest the following book though which will give you a basic intro https://www.amazon.com/Fundamentals-Smart-Contract-Security-Richard/dp/194944936X