A core part of working with UI is being able to manipulate UVs. This course will show how to do this. The course will cover what UVs are, and the relationship between UMG and UVs. It’ll explain what 0-1 space is with respect to UVs, and then provide hands-on examples of how to manipulate UVs in different ways.
https://dev.epicgames.com/community/learning/tutorials/Y4Kb/unreal-engine-using-uvs-for-tech-art-and-ui