When I'm alone I'll wear a full suit, because dressing up makes me feel nice, but I lack the courage to go full "retro men's fashion enthusiast" and dress up like it's 1939
Have a look at Darcy Clothing! They produce clothes styles from c.1600s to 1950s.
There's some nice stuff there for both men and women. Comfortable and stylish, imo.
Example: https://www.darcyclothing.com/apps/bundles/bundle/24247
Man, acquiring the pieces isn't even the hurdle I'm trying to cross right now. It's straight up a matter of confidence. Like. People will see. And they'll ask stuff like 'what's the occasion' x.x
Yeah, that's the whole being confident in your own skin thing. Tricky. Why not try clean, neat casual clothing first, like jeans/slacks, nice shirt, good shoes and put on a nice 'internal' suit first, good manner, curtesy/politeness, easy demeanor, well groomed, etc. that reflects what you want to be, or the reaction/response you seek from others. For those not terribly fond of the limelight/attention, any forced affectation will be pretty hard to carry. Sometimes it's just easier to blend in, depending on town, city, country. Sorry, got lost pondering your predicament. Hmm, tricky. Good luck.