I haven’t seen that page in UE5 since it was introduced. I didn’t even know there is a browser inside it.
Anyway, it seems you have messed up your UI arrangement, if from UI you mean the UE5 Editor UI.
From Window Menu, Choose Load Layout and then default Editor Layout. hope it fixes it, otherwise, try Repair from Epic Launcher ( I assume you installed it from there and didn’t compile it yourself)
One more thing, I just noticed the name of map you are looking at is similar to a tutorial. If you are in a tutorial about UI, then what you are seeing is expected. it is part of the tutorial on how to create UI, the tutorial itself will tell you what to do with it