Spider-Man: No Way Home (2021)
Dread Pirate Robert 6 points 2 years ago. (Contains Spoilers)

Can someone explain to me what the Venom bit was about at the end? Why was he there, where did he go? Etc.

Honest Review 1 points 2 years ago. (Contains Spoilers)

He was brought into that world because he knows Spider Man same as all the others. He works for same paper as Peter. Then when that last spell is cast he goes back to his universe. Also foreshadowing the setup for Venom being introduced into the Spider Man franchise with that piece of him that was left behind.