Girls, please help, I want to put a coil, I don't know which one, and …

Girls, please help, I want to put a coil, I don't know which one, and is it even worth it? In January I'm going on vacation, but my period hasn't come yet, but I already feel like they'll be coming soon, I'm worried about the vacation, how to swim with them, I read that after the coil, periods flow abundantly, or to take a month of medication to be