Quick Question about making a custom Healthbar and Pause Menu UI

So I’m working on an Action RPG game, while I was just surfing Youtube for some ideas I came across Rei PREV who’s UI elements look like they exact thing I’m trying recreate, such as Healthbars, MP Bars, Menu, etc. So would all this be done in photoshop?

The icons in the skill tree, for sure ( of any other package, like GIMP ). The bars could be using UE default elements, but you can make them look like anything you like using a photo package of course…