I tried to do a pull up but all I didn't have the strength for it. What excercises would help me?
Try to do pull-ups with your legs still on the ground. For example under a table.
Back And biceps are the main muscles involved. So if you have access to a gym; Bicep curls, curl to shoulder press, lat pull down. Bent over rows will all help. Do 5 sets of 5 to increase strength. And keep trying. Do assisted Pull ups where you are not pulling up your whole weight, and try just hanging from the bar to increase grip strength. Good luck!