Can I go for exchange advertised in Nigeria by comedians?

I like watching comedy a lot, I noticed comedy have turn to business in Nigeria, all them are doing it for one reason, the reason is to be rich, they are using it for advertising and they are paid.

The question I want to ask is that many exchanges they are advertising I have not heard of the exchanges before, what are you know about the exchanges, are the exchanges safe to use to buy bitcoin true true?

What I mean are crypto exchanges.