Beginners devs on GameMaker: Studio 2, are usually facing relatively early on their gamedev journey a common challenge, which is managing the resolution of their game. Nowadays, on most platforms and especially the mobile platform, there are countless different screens of various sizes and aspect ratios. The Advanced Resolution Manager for GameMaker: Studio 2 is hopefully a handy GML script that will do the logic/code part of the job, letting you focus on other aspects of your project.
The Advanced Resolution Manager for GameMaker: Studio 2 is absolutely free (MIT License), open source and very easy to use. At this link you will find the source code and three example projects; one of the example projects, is about handling the dynamic orientation.
Here is a sneak peek: