Yesterday I started on an idea that I promised to finish today. I'm gonna make this one quick.

When going into a new situation, and you're not sure why you're even there, remember your core strategy.
When you feel like a fool that's leagues outside of "where you belong," focus on your mission instead of yourself.
What matters is what you set out to do; what you set out to change, not who you think you aren't yet.

An Example

"This world is a madhouse, and I'm tired of pretending it's not."
That's my personal "strategy," obviously in the form of a statement/catchphrase.

As I'm looking more into becoming a salesman, that line is what drives me. There's too much insanity that's gone on for too long, and I'm going to help anyone I can to escape from it. If I'm selling something new to me, I'll start by looking at what came before it and find whatever crazy-making it was doing to make itself seem important. Once I know how the old product/service/philosophy was extorting people via their own ignorance, I have a clear path forward on how to sell the new thing: the new thing, even if it's not (yet) perfect, will render all the chronic fraudulent suffering you've known into nothing more than a bad memory. (Of course, the new whatever has to actually do that!) I can go from staring dumbly to selling dramatically right from jump, since I have a basic universal idea to default to.

If I ever start to get lost in my own doubts, I just have to remember my shtick: since the world is a madhouse, what I need to focus on is how that madness is going to undermine itself. Once whatever I think I can't handle has been laid low by its own machinations, all I have to do is position myself to be out of the way of the falling rubble. Even as the world shifts around me, I keep a steady constant idea to focus on.

There's always a way forward.
There's always a way out.

Starting over is hard. Don't do it unless you absolutely have to. Maintaining a fundamental shtick keeps your "square one" locked in no matter what. You'll always have a baseline of positive momentum.

You may think that having no solid core identity will make you adaptable, but it really only makes you malleable. The easy mistake to make is to think that making no commitment will spare you from making a wrong move: yeah, that's a blunder all on its own. "For every action or lack thereof there's a consequence," as the song goes. The question is only whose failure do you risk experiencing; yours, or somebody else's?