Minecraft launcher takes a while to open & game crashes

Issue/detail:

When I open my launcher it doesn't open instantly and I have to wait a while, after waiting a while the launcher pop up on my task bar. My launcher used to work perfectly fine and I didn't change anything to cause this and even if I did I don't remember doing so. The launcher is in task manager since I opened it and checked. The launcher hasn't load anything and it said that it is not responding. I also have another problem is my game crashing often here is the crash code I usally get. ( I use forge and have skyblock mods on since I play on hypixel skyblock and my mods havent caused me this problem before ) I give forge 2gb or ram since 4gb bugs my game. If anyone knows how to fix this I would really appreciate this since this problem is annoying and I cant enjoy minecraft.

Error message:

The game crashed whilst tesselating block model Error: java.lang.ArrayIndexOutOfBoundsException: -348
Exit Code: -1 Error: java.lang.ArrayIndexOutOfBoundsException: -348 Exit Code: -1