How can I make it so my UIS are in the same position on all screen resolutions?
This post by Itsyourdriver is a collection of several great tutorials, including positioning GUIs for different screens:
I believe this is what you are looking for (you can also find this in the original post):
I had issues with this for ages, I ended up using the plugin AutoScale lite, since (at least for me) it’s basically just a couple clicks and your UI is all nice and lined up with any res. Check it out here: [Plugin] AutoScale Lite for GUIs - Scale your UI