One of the tips for processing feedback is “to convert it into action items”.
What should you do if you don’t really know what to do with the high-level feedback you get?
Example: I got the feedback that other engineers don’t think that I understand the framework/library we’re working with deeply, not understanding the patterns and whys behind things that we do in our project, not knowing how to use different/“better” patterns.
Unfortunately, they didn’t give me a specific example, so I’m unsure on how to convert this into an action item.
We don't have mentors, so there isn't anybody who can "teach" me, except learning from code reviews, asking to do more pair programming, etc.
My idea would be to study up on “design patterns”/best practices for the framework we’re using, but I’m unclear on if that would really solve the issue.
It's important to be deliberate about proactively following up and acknowledging the feedback, even if it's vague. For example, in the next code review, could you write an extra paragraph explaining why you chose the approach you have? This proves that you're thoughtful about the best practices.
Then tag the person and get their feedback. At the very least, they'll appreciate the work you put in, and at best, this will convince them that you know your stuff.