Cat Went Missing—How Do I Even Start Looking?

So, plot twist: I left my cat with a friend while I was away for a few months. Came back, and surprise—she’s been missing for three weeks. My friend only told me when I walked in the door. He says he put up flyers and asked around, but honestly, I don’t think much else happened. Now I’m scrambling to figure out what to do. I know I’m late to the search party, but I’m desperate for any advice. She’s microchipped, but I’m not sure what else I can do at this point. Should I be checking shelters every day? Is there a way to boost the search online? If anyone’s been through this, please drop your best tips. I’m overwhelmed and just want her home. Please keep it to advice and no blaming—my nerves are already shot. Thanks so much. <3 #LostCat #PetSearch #Microchipped #Pets #Cats