career as a comedian

Many wants to be a comedian - very few can live on the income or even get a name.

There are courses for becoming a comedian but you hardly really learn to be a comedian that way.
Two important things are your personality and your ability to get contact with the audience. Last but not least the manuscript which is the basic for the show.
There are different kinds of comedians. One is where the manuscript is the central. Another is the comedian uses his personality and the third one build up his show with talking with the audiance.

Many comedians have started as actors and or writing scripts for other comedians.
If you have no experience one can start working first without pay in a club and work you way up.

Good luck.