I simply log in, it shows me the home page, then, as I click Unreal Engine, it suddenly says, “EpicGamesLauncher has stopped working. A problem caused the program to stop working correctly.” Is there anyway to fix this?

Did you delete something from the engine source? Something in the folder “Slate”. In case you develop on mobile, to shrinkt the package size, maybe you deleted the content of this folder and now you have to replace it.