Will my worlds be preserved if I delete Minecraft?
I reset my phone and I forgot about my Minecraft world until now.
Will I lose it for good or will it still be there after I log in to my Minecraft account?
If you deleted the app from your device, there's a chance that the data of the minecraft world has been saved, and you'd just need to re-install.
If you fully reset your device, the world is gone - it isn't saved to the cloud.