Was the moon landing fake using CGI? No, this idea is impossible
(picture from the Apollo 11 moon landing Wikipedia Page)
There is an interesting theory that says the moon landing by the crew of Apollo 11 was filmed using Computer-generated imagery or in a studio on Earth.
I am not sure where these people get their ideas from as Computer-generated imagery (CGI) at the time was not that good. In fact, it was rubbish, and not that convincing, you can see examples of this in the picture and the article below, entitled The History of CGI in the Movies.,
Also, movie special effects in the 1960s were mostly done by models, animation, or other practical methods, not computers.
(Picture above from article "8 Bit Sprites to WebGL: How Computer Graphics Have Changed the World" a link to this article can be found in the reference section of this blog post)
They also did not film it in a movie set on Earth, as the lighting and movements of the Astronauts would be all wrong. It could have only been filmed on the moon.
As to the question, some moon landing deniers used in the past to justify their claims, which is
"How did they film the Astronauts coming out of the landing module or LM, as no Astronauts got out at this stage"
This issue can easily be solved by the fact that there was a remote camera mounted to the side of the landing module, or LM, which was moved into position and started filming before the astronauts got out.
(The weird ideas that moon consistency theorists have can be easily researched and easily debunked, probably even by a child moon landing fan as it is that easy and not hard to understand.)
This proves that consistency theory people do not know anything about the subject they are debunking and don't even have a basic understanding of history, science, or photography for, that matter.
Below is an interesting video by the MythBusters as they dismantle ideas, followed by moon landing deniers.
Also, check out photographer Dave McKeegan's video and his YouTube channel below where he debunks moon landing theory claims especially the claims that the pictures and videos of the moon landing were faked on Earth.
References:
Take note, consistency theory, people, maybe the meme below mocking you is correct, and the meme below shows 1980s CGI, not 1960s
Also, check out my history blog version