It really not too complicated.
The purpose of a gedcom file is to exchange information between genealogy programs. The data is in a standard format, so in principle it does not matter what software generated the file, nor what software you import the file into.
The gedcom file is a text file which is essentially unformated, other than each bit of information is on one line.
Gedcom files are not intended to be opened, like a word processor file, and worked on, but rather to be imported into a genealogy program.
An important feature is sometimes when these files are created you get a file with a “.txt” extension instead of a “.ged” extension. Genealogy software cannot read a txt file, and this is where importing the file can fail. Change the extension from txt to ged and the file should import without issue.
Your genealogy software will have a menu option to import file. Click on that and follow the prompts and you should have no issues.
I use the software Marion mentioned, and it works nicely.
WikiTree has a different, more labor intensive process for importing a gedcom. I have read about it, but have never done it myself. If you go to the WikiTree help menu there is a link for gedcom files. That will give you the details. Also, there are frequent discussion about the process in g2g.