Yeah what Ryan said, the word is "pivot". To further describe the use, pivot has many definitions. In this context it means "the next step in a project or plan" In the video, the man explained that they started a fundraiser and immediately raised some money to send kids to college. The next step is to start summer schools for these kids. This is the pivot. And for that they need to raise more money. Though the man said "gain pivot", I think "make pivot" sounds more natural and it's "more" grammatically correct in my opinion. Don't worry about it though. Even native speakers don't use the word "pivot" this way in daily conversation.

The literal translation is: "About Japanese greetings, understand?" From the sentence, it is implied that the speaker is talking to you (or another person). The "about" in the translation about comes from the "って" after "あいさつ". So the normal translation is: "Do you understand Japanese greetings?" Hope it helps.

Yes all three are perfectly fine