I got a major revision and I will prepare a revision letter. The editor asked me to review my manuscript for grammatical errors, in addition to the scientific comments he made. Should I present all the grammatical changes I made on the manuscript one by one? There are lots of minor changes (i.e addition/insertion of commas, "the", "a/an").
Since they haven't pointed out what mistakes you have, it is unlikely they have a list of errors they have found; therefore, enumerating your changes is pointless. Also, since you got "major revision", a good chunk of your text should be changed anyway.
Just make sure you double check the language before resubmitting, preferably by someone else (native speaker would be ideal).
Should I present all the grammatical changes I made on the manuscript one by one because there are lots of minor changes (i.e addition/insertion of commas, "the", "a/an")?
This seems unnecessary. What I usually do is report all the mentioned grammatical errors, and then just remark that I fixed all of them.
That being said, if there are so many grammatical errors that this is an actual problem for you, you definitely need to tighten up the writing of your paper.
I very much doubt they care for you to acknowledge every problem they point out to you, they just want you to fix them (and others you might find in the process). If you disagree with some of the suggestions, then it makes sense to speak up and explain your reasoning (should probably do it in the text too, if whoever did the revision didn't understand it, chances are it will confuse other readers too).