You should ask in "questions section" but I'll answer you anyway.

"haga" comes from the verb "hacer" is used in this sentence because it is a possibility and it means that "I might become a computer programmer but I haven't decided it yet".

By the way, in Spain we say "ordenadores" and not "computadoras", but programador informático implies that is for computers, so you don't need to say it.

So, the sentence woud remain like this:

Tal vez me haga programador informático pero no me he decidido aún.