I enjoy clapping in church while choir sings. I want to buy a Cabasa instead of a tambourine. Do I need to take lessons just for this use.?
Most hand held percussion instruments are, almost by definition, simple to play. Such as the tambourine. The cabasa is hardly any different. Basics are hold the handle in your dominant hand. It can be shaken, like a maracca, also hit with the other palm, to produce accents, while shaking, or just on their own. Don't forget the main way to play, rolling it with dominant hand, while the other palm allows the beads to roll in it.
A clever technique is spinning it, so the beads continue to turn and rattle. You need to experiment with other ideas, which will probably come to you in certain songs. I don't believe there are any exams available to be taken on cabasa, although there are those for a whole raft of percussion instruments together.
So, simple answer, no, just get on with it, enjoy what it can do, and take its sounds production possibilities as far as you can. Two could be more than twice the fun!