.txt to Unreal Engine and pack

Good afternoon,

In an Unreal Engine game I have opened a . uasset file via “FModel”. I copied the script into a text editor to edit the script.

Now how do I get the text file into UE4 Editor 4.23 to pack it and have a . uasset again?
Is it really only about Visual Studio and Blueprint in UE4 Editor?

Greetings