MSGO has an installation wizard as well as a PDF on how to run the installation process. Follow the instructions until it’s done.
Then install the latest version of the Morrowind Code Patch, which has options that are fairly important to smooth gameplay, such as showing whether an object is owned or not. https://www.nexusmods.com/morrowind/mods/19510
Copy the Morrowind Code Patch files into the Morrowind directory (make sure to merge the correct folders so the Data Files folder merges with the Code Patch’s Data Files folder, etc.) and rerun the code patch config exe file to select all the new options you want.
That’s it. You can play Morrowind now if you want. You’ve updated the graphics and functionality to the point where the game is playable. However, you’re missing out on a lot of great content.
What to use to install mods:
Once that’s done you can install mods with either the Nexus Mod Manager (which is what I did because I was used to it from Skyrim modding) or Wrye Mash (which you’re gonna need anyway): https://www.nexusmods.com/morrowind/mods/44386/
Either way you’re gonna need to make sure that every mod you download is repacked correctly. The archive should contain a folder labeled Data Files, and all mod files and folders should be inside of that. This is an essential step.
You’re gonna need to sort your load order and make a patch with Wrye Mash to make everything work together every time you install and test a mod (or batch of mods if you’re lazy like me.)
There’s a few mods I find to be so useful or enjoyable that they’re just essential to any Morrowind game I play.
Julan Ashlander Companion Mod (There’s a reason he’s first! He adds so much to the main quest that I can’t imagine doing it without him!): http://lovkullen.net/Emma/Kateri.htm
As a disclaimer, I am neither a mod maker nor a programmer. I’m just an average person who is fairly computer literate, and knows how to follow tutorials.
I have not finished playing all the mods I have installed, so I cannot tell whether I want to recommend them yet. I will be adding to this post in the future.
Also, texture replacers are a matter of taste, and honestly I’m using so many that it’s gonna have to be a subject for a different post.