I'm not quite sure what look you are wanting here, but I've got some tips on where to start.
First- remove things that make you look dated, or you dislike wearing them. I'm afraid (for mumsnetters) that that would include skinny blue jeans for starters. Just changing up one thing, like getting some wide-legged trousers or jeans and then starting to think what would go with those is very helpful for me, anyway.
(I'm not going to argue whether skinnes are round the corner again, some people can get away with a black skinny like Claudia, but she's very confident in her personal style and the OP is not).
Or go the dress route, I can't help with that as I find midi-dresses slightly dated looking and I'm short so they don't work for me, but you are taller and might look good with a midi denim skirt or something like that.
If you go on Vinted, I'd search by fabric, and by brand- so the brands above, for example, or search by wool, cotton, cashmere, leather, only nice quality items then pop up (with a few fake ones scattered in there).
Decide if you like the Scandi look, if you do, then I'd go for linen shirts, a proper wool coat (as the very cold time where you have to wear puffa jackets is passing) or a wool jacket, and white/navy/green t-shirts underneath. I don't entirely go for this myself, but I prefer plainer colours and lovely fabrics which are from that style- I don't like it all too outsized or covered up though.
I also then dress that up with lots of lovely jewellery which stops me feeling my look is so plain.
Great hair too.
I am shooting in the dark here, so if none of this appeals, that's fine, just give us some more clues to the type of look you want (as you say you don't want to look like everyone else, somehow).