I agree with a previous poster that you should wait until you are comfortable with your new job before looking for supplemental income. I started at CVS Minute Clinic as a new grad and have found it to be a great starting place. Yes, there are clinical guidelines that we have in place to guide our care, but these guidelines that "guide" us are just that. We are expected to treat within them as they are made from evidence based practice, but we still have autonomy and can treat outside the guideline too as long as we are appropriately documenting and including rationale.
I have seen a lot of providers comes and go (experienced and new grads). Just like any job, not everyone is cut out for this type of job. People sink or swim. I know some providers who have left MC only to try out a different job, and then return. I have also had many coworkers who start here as a new grad and then after getting experience, have found other great jobs (hospital, private practice, etc) and have been very successful.
While we do not treat everything an urgent care setting can, we do see more critical conditions. The provider works alone so must know when a more appropriate referral is needed. Sometimes patients come here because they simply don't know where to go.
Good luck with your new job! If you have any questions about MC feel free to message me. There is also a 'Nurse Practitioners in retail health" that you can join to connect with your peers.
I have coworkers that get supplemental income by picking up extra shifts with different MC locations. I also have some that work PT for other companies/practices. If you are worried about losing skills, then I think picking up extra hours somewhere once comfortable with your FT work as a new grad would be a good idea.