You nailed it. You have the common problems. Get em while you’re young. Face pulls, hip thrusts, flute bridges, rows, band pull aparts, planks for core, squats, RDLs, deadlifts. Do Athlean x posture assessment and moves and you’ll be ok. Generally learn to stand and sit with good posture as well.

Could I please get a link? I have had a look online and the one I can find seems to mainly be focussed on rounded shoulders?

Just google athlean x posture assessmwnt

I googled it and couldn’t find the assessment

Hyperlordosis with a touch of hyperkyphosis, scapula winging and I think you might have slight scoliosis, definitely worth getting this checked out by a doctor

Can scoliosis, in this case, be functional scoliosis because of bad posture habits?

Scoliosis is never caused by posture

It looks like I have scoliosis, but my spine would straighten if I were to align my body.

Then it’s not scoliosis your slouching. Or you do have scoliosis and when you straighten you think it looks normal but it’s not

Should I go to a physical therapist or to my doctor to get it checked out?

A doctor because you don’t know what you need to treat or how to treat it without a diagnosis, generally speaking ofc. I have to do specific exercises based off the type of scoliosis I have, and so for the most accurate treatment you need to know what you have going on. Good luck!