I am 23 with minor crookedness in my teth. braces or invisalign, now or later?

Sooner the better: And as for your first question, you need to consult an orthodontist.

Your choice: The answer to your question will depend on the amount of "crookedness" and if/when you want it corrected. Schedule a consultation with an orthodontic specialist who can better answer that specific question.

Minor?: Is that your assessment or an Orthodontist's? There's a reason for front crowding, and sometimes the fix is easy, sometimes hard. The longer you wait, the more crooked your teeth will become, the harder/longer/more expensive to treat. Know that Braces are still the gold standard, twice as effective as clear aligners. See an Orthodontic Specialist for an initial evaluation (usually free).

Crowding: Either option may work for you. See an orthodontist or a dentist to discuss your options. Generally it is better to do this sooner rather than later while the crowding is minor as thing can get worse over time.

Orthodontics: Both methods have their place. Pros and cons for each. I recommend you see an Orthodontist and not a General Dentist trained in Invisalign only. Then discuss your options and ask what is best for your particular circumstances.