Can somebody "explain like I'm 5" the Russia/Ukraine situation?

Here are all the conflicting things I have heard and read:

~Ukraine wanted to join NATO, Russia didn’t like that, so they invaded. Some people say it’s not that simple.

~Some people have said this has been in the works for years

~Some people say this has been in the works for months

~Some people say this is just random and out of the blue.

~Some people say this is entirely fake, and all footage is from years ago.

~Some of the footage is actually from a video game

Assume I know NOTHING about this, because I don’t and pretty please, explain it to me!