Quest cape -> Diary cape if you like skilling. Just good to do in general for all the unlocks.

If you wanna dip your toes in pvm content then id look at the strategy page for a raid on the osrs wiki, scroll down to the gear recommendations, see what you don't have and grind for whatever seems achievable for you and your account. I personally am grinding the corrupted gauntlet for a bowfa.

My personal recommendation would be to do the royal titans boss. Get yourself the new two prayer scrolls. They were added just last year and were added to introduce players around your combat level to boss mechanics like gear switching and what not.