It’s probably best to look up tutorials and guides for this. At the most basic though, Scale is a percentage from 0 to 1 where 1 is the full size of the screen (or the Frame that the GUI is inside of) and Offset is actual pixels. You need to use both. Some GUIs should scale, some should not. You usually need to preserve aspect ratio, but not always. It will require experience to get it all figured out.
I use AutoScale Lite - Roblox to fit all devices, just select all the frame, labels, buttons, etc and use the “Add constraint” and “Scale text” for the textlabels and things like that. I usually convert units to scale but not sure if it makes a difference.
How do I scale a GUI 1 way, in like a direction, using script/tween. If I wanted to scale the GUI on the Y axis incrementing vs decrementing. How is that done? It seems like I can only edit that in studio mode resizing the GUI in either direction but it only shows on the Y axis as a increment or decrement regardless of which 2 coordinates (top left corner/top right corner) and vise versa.
Im not an expert on UI and I can’t test weather im right or wrong but try using :TweenSizeAndPosition since the position changes every time you scale GuiObject | Roblox Creator Documentation But if you only want to tween the top corner points, I think :TweenSize should do fine