Minecraft crashes when I select external and crashes after loading too

So you know how there's a "Application/External" option when you update the game so I have a lot of texture packs I don't know if that the problem loading Minecraft, to be exact when I open the application it freezes at 71% and then crashes and I'm ready scared that I may lose one of my survival worlds which I have a had for a LONG TIME and even when it opens one time, I wanna put on my skin it crashes again??? I don't know if its getting overloaded, loading assets or something I don't really know, can someone please help me :')