It's important to dream. To take some time and think, "wow, wouldn't it be cool if...".
Once you have a dream you have to get super clear about it. I want to be an improviser. Okay, great dream but what does that actually mean? I want to perform on a weekly basis in a show I've created and produced on a team that I have cast vs I want to perform on a team that is under the umbrella of a theater with guaranteed stage time and the theater has cast and we have designated performance dates, rehearsals, and a coach.
Those are both being improvisers but very different details. Each of those would and should be a different journey on how to get there.
Once you have the specifics, you have to put in the work. It won't always be easy, however, if you want to succeed you have to put in the hours, say no to other opportunities, stay focused, and stick to your plan.
This isn't just for improv. This is for life. So dream and dream big then go get to work!