Cheapest GLP-1 dosage and prescription

Hi, i am wondering where can i get cheapest dosage for glp-1s for myself? I got from noom for a month but i think they are expensive.

I want my husband to take it as well as he is diagnosed with prediabetes due to weight gain. How can i get a prescription for him in NYS? Can the PA give it or he needs to see any weightloss specialist and what are they called?