Usually it takes a little while, but I’ve found ways that work, at least for me, to make the process a tiny bit faster.
See a dermatologist and ask for a prescription acne cream. Typical brands like Proactive didn’t work for me and even made it worse. Prescriptions are more reliable.
Wash your face every day with a very basic face wash. (By basic I mean you can use dove soap if you want. Just nothing with harsh chemicals or anything fancy.)
Last, drink water and don’t touch your face.