Hi, if you use an airband radio you have to have an operators license to use one. Usually a training flying clubs will run courses as part of pilots PPL training. The handheld airband radios are really aimed at people needed to talk to airtraffic control, airfields etc and not a "chat" radio.
I could be wrong and happy to be corrected but I don't think a lot of Paramotor pilots use an airband radio but do use other radios like PMR446 license free for group flying and training. I'm sure there are lots of posts on what radios people like.