Question about medical card

Hey everyone. Turned 18 a couple days ago and was considering getting a medical rec from NuggMD online. I live in california so it’s easy to get weed, but i would prefer purchasing from dispensaries which is why i want the card. My question is about the process. Can you can get the online recommendation, bring your CA ID, and purchase from a dispo? Or do you have to get the recommendation verified by the state. If anyone has experience with NuggMD or other online medical rec services you recommend i would appreciate it! Thank you.