How to get rid of acne???

Maria

My skin used to be pretty flawless, and lately I’ve just been messing with it. Undergrad was a stressor along with sleeping with makeup on as a result of studying. Regardless of that, I will get these pimples that turn into like pimples under the skin. They don’t really get red or have puss. Has anyone else had these pimples? What are they called and what can I do to help with them?

Also how can I get rid of these dark spots because of my pimples?