I want to be an actor but I dont know how?!

I want to be an actor but I dont know how?

If you're in school, you can join the drama club, be in a play.

If you live near a major city, there will likely be several casting agencies in the area (just Google that). You'll have to pay a fee to obtain a resume or whatever, and you could sign up for casting calls from there when the agency's site notifies you of one. The agency might post notifications of produtions looking for extras as well, so you could be an extra first to gain experience of being on a set, and maybe try putting in a word about yourself to important people (I have no experience with any of this (yet) but am only using logical guessing based off what I understand).

If there are any theatres, you should check if they're casting extras as well. There's a certain name for the theatre version of an extra, but I can't remember what it is. Anyway, it could be like the equivalent of being a movie/TV extra.

There are a lot of places where you just kind of sign up and maybe the people will contact you. But, I recommend you just go out for something all the way -- especially if it's acting, since you are an actor -- and just personally head-dive into it to gain a better chance of being noticed.