How can I give myself a damaged item on 1.13?

Solution 1:

The /give command in Minecraft 1.13 has been changed to this format:

give <player>[<selectors>] <item>[<NBT>] [<count>]

Knowing the NBT tag for damage being Damage, I wrote this command. (Don't currently have minecraft installed to test it, but it should work.)

/give @p minecraft:elytra{Damage:50} 1

This page on the /give command and this one showing what tags you can apply to items should be helpful in understanding how to use them.