When it comes to improving your face, there's hardly anything that will magically change your appeareance, unlike weightlifting cutting and tanning would for your body. However there are some things, I'd consider being actually useful:
- Skincare - kind of a no-brainer but even if you don't struggle with acne or pimples it increases your skin quality and therefore your overall looks
- Weightloss. Broken down less fat equals a more defined face structure, hollow cheeks and a chiseled jaw line. To enhance that effect, you can debloat (drink a lot of water, eat high potassium food and avoid sodium, which is in salts).
- Honestly, 99% of face exercises is just cope. The only ones I would recommend giving a shot would be mewing and UUDD (look it up, stickley has a video explaining it).
Keep in mind: None of this works if you aren't consistent.
Edit: If you want individual advice, which is less broad, it would be helpful if you would upload a picture of your face and one of your side profile.