Hello MineX server,
creating a custom UI layout system along with all the required layout math can be frustrating for beginners. By asking this question I am assuming that you have no prior experience with custom UI systems in general. For that reason I recommend you to use the DGS resource. It was created by renowned members ( @xLive and @thisdp) of the MTA community and is based on the dx family of drawing functions. How about you give it a try? ?