Trying to load a world occasionally makes Minecraft get stuck in either the "Loading Resource Packs" or the "Generating World" screen dialogues with the game tips, and the world never loads. It seems to be a minor bug that can be worked around by closing the game and reopening the game.
Linked issues
duplicates 1
Comments 1

Thank you for your report!
However, this issue is a Duplicate of MCPE-34379.
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