If you have specific questions or doubts then I am sure you will get a lot of answers. For the overall procedure and step by step guide of how to perform MM-GBSA calculations using Schrodinger, you will have to consult the Prime user manual and How-to guide available on Schrodinger website. They explain the entire process in great detail. You will also find many detailed step by step tutorials on the Internet with a simple google search, like this one (http://gohom.win/ManualHom/Schrodinger/Schrodinger_2015-2_docs/maestro/help_Maestro/prime/prime_mmgbsa_panel.html). You can try on youtube as well.
For MM-GBSA calculation, use Prime module of Maestro not Glide. You can directly import the output file of the docked complex and add it to calculate MM-GBSA. Or alternatively you can define the protein and ligand to calculate MM-GBSA.
As Glide is basically for docking calculations the docked complex output from Glide can be used as input in the Prime module for energy calculation (MM-GBSA). the output of this process will be located in the selected directory. The folder consists of 6 files of which the out.csv file (excel file) contains all the energies of the complex. Let me know if this helps.
I have a problem with running the MM-GBSA calculations. I use the xp docking file (pose viewer file) and keep the parameters on default settings and run it, unfortunately, the process fails after few seconds.