Alright alright hold your horses, you can't just jump in the portal and fight em, first you gotta prepare, i recommend diamond armor enchanted with sharpness V for the armor, bring a sheild as well. for weapons bring a diamond sword enchancted with looting 3 and a bow enchanted with feather falling, you also need ender pearls (at least 15), tnt (at least 20) and flint n steel, i say to bring 5 stacks of arrows and a few stacks of dirt

Well its finally time, you got to the portal and got your items, but now the real fight starts. if you hit the ender dragon he will regen HP from those weird things on the obsidian pillars, but luckily you can break them, use the blocks you brought to build all the way up to the top of them, then place a block of TNT and light it, then immedietly jump off the pillar so you don't get blown up, but some pillars have cages around the healing object thingys, for those ones you wanna climb up with blocks, place down a peice of TNT and light it, but don't jump. swap to your bow and arrow while the tnt is about to explode, get hit by the tnt, this will break the cage and send you off the pillar, quickly face the healing object and shoot it with an arrow while you are falling, repeat this until all the healing things are dead, then just shoot the ender dragon a bunch lol idk