How do I get a prescription for Zoloft or Paxil?

I have bad anxiety and have been going to therapy but have been thinking of going to a separate doctor to get a prescription. Do I have to go anywhere special or could I go to a walk in clinic? Also, my insurance only covers 40%, so how much would I have to pay out of pocket?

** also if you have any suggestions for a med I should look at let me know pls ❤️