I’m 68, retired and enjoying my second childhood 
doing what I want, which is at the moment Fritzing. Git without github is reasonably easy, there is an excellent free book available as a pdf. For a html document the branch / commit cycle is fairly easy (and I understand there is a graphic version which is even easier). The part that is tripping me up is getting my changes back to my fork on github, getting them local hasn’t been a problem. Worth at least a try because it sounds like it will do what you want (be able to go back to any previous version that has been committed).
Peter