The slightly raised bumps are fordyce spots. Your foreskin does appear slightly tight, so you may have phimosis as you mentioned. Are you able to retract your skin when your penis isn't erect as pictured?
I've done it a couple times before when it hasn't been erect, with force but not so that it caused pain. But I had to move the foreskin back over the head of my penis after which was difficult because it didn't smoothly return back, it was like it got stuck.
You can try slowly stretching your foreskin when flaccid. You may be able to gain a little more space to pop your head out when erect after a few months.
Okay, I'll try to make sure to do that everyday, I'll probably give an update in a couple of months then. Thank you
Good you are stretching as it's the best way, but it does take months to years. Generally include some form of masturbation to do this as it's more fun.
Regarding sex, when you are ready, you will have to have some trial & error with your foreskin for the best comfort. For some, it's by leaving the foreskin forward, others need to pull it back before fully hard. I'd say to try with a DIY toy (instructions on most amateur p..n sites) unless you have a understanding partner.
Prepare for some embarrassment & rejection from a partner, but don't let s/he stop you from trying with another person. Best to talk about the situation before getting too horny.
Also, keep asking questions :)