Don't stop trying - that's the hardest part. You'll probably die a lot if you just started PvP since a lot of people have been playing the game since launch and not only have better gear but have the maps memorized. They are used to the radar, know you are coming around the corner and fire before you can see them. Just looking over your gear and I would say trying to upgrade your weapons and armor would also help level the playing field. Bungie says all the gear is normalized (which is it) but that doesn't effect the weapon / armor perks. Weapon perks like Tracking on rockets or Final Round on a sniper can make for easy one hit kills. Armor perks can increase melee speed, reload speeds or give you more ammo for a given weapon.