I’m slightly confused by the question but if I understand it correctly. Your asking about in the finale when they see their S6 selves?

@LR2159 Yes, I'm talking about the finale where they see them S6 selves.

And it’s the same time travel as endgame(quantum realm) so it’s not an alternate timeline unless they took something. Which if I remember correctly, they didn’t

I know but like I don't understand, who it was possible that there were 3 same people at the same time (Jemma from S6, Jemma from S7 and Jemma in space, etc)?

2019 Fitz and Simmons go to space with Enoch to start their plan, their daughter Alya is born. They live to the year 2023 in Theta Sepentis. They then travel back to 2019 when they originally left.

2023 Fitz and Simmons arrive back in 2019 to save the team in the temple, while their 2019 selves are heading to space with Enoch. Fitz and Alya stay in 2019 in the Zephyr pod. 2023 Simmons travels with the team to 1931 and they create an offshoot timeline till 1983.

Using the quantum realm 2023 Fitz travels to the off shoot timeline and retrieves the team to take them back to their original timeline in 2019. While they are in space The 2019 and 2023 versions of Fitz and Simmons and the rest of the 2019 team are running about on Earth. They then all go down to save their original selves to complete the time loop.

So, there's 2019 FitzSimmons, 2023 FitzSimmons who haven't time traveled to before 2019 yet (we'll call them "2023 FitzSimmons NT" for "no travel"), and 2023 FitzSimmons who are returning from the alternate timeline (we'll call them "2023 FitzSimmons R" for "returned").

What happens:

• Enoch tells 2019 FitzSimmons they have to leave

• 2019 FitzSimmons go to Piper and Flint and ask for help

• 2023 FitzSimmons R arrive with the team

• 2019 FitzSimmons, Enoch, Flint, and Piper land the Zephyr

• 2019 FitzSimmons and Enoch go into space

• 2023 FitzSimmons NT return from having spent four years in space together (2019 FitzSimmons will become 2023 FitzSimmons NT)

• 2023 FitzSimmons NT go to Piper and Flint and ask them to protect the Containment Module, which contains Alya and 2023 Fitz NT

• 2023 FitzSimmons R (and the rest of the SHIELD team in hazmat suits) help 2023 Simmons NT retrieve the 2019 SHIELD team from the temple

• 2023 Simmons NT tells the 2019 team about the Chronicoms attacking them while the hazmat team, including 2023 FitzSimmons R

• 2023 Simmons NT and the 2019 team leave for 1931

• The temple is destroyed and 2023 Fitz NT leaves for 1983

So, until the 2019 team left, there were three versions of FitzSimmons: 2019 FitzSimmons was in space preparing to study the Time Stream, 2023 FitzSimmons NT had just returned from studying the Time Stream were about to leave for 1931, and 2023 FitzSimmons R were helping the SHIELD team which had just returned to defeat the Chronicoms. So it was only for a short while, but there were briefly three versions of FitzSimmons existing simultaneously. After 2023 FitzSimmons NT leave (Simmons going to 1931 and Fitz going to 1983), there are two versions (2019 FitzSimmons and 2023 FitzSimmons R) until 2023, when 2019 FitzSimmons return to 2019.

I hope this helped, I tried to make it as not confusing as possible.

Oh okay, now I understand everything better, thanks to both of you. So if FitzSimmons had done something that wouldn't have completed the time loop, this timeline would have changed, right?

Theoretically. However, that was never an option. FitzSimmons were always going to return to 2019, were always going to go to the other timeline, and were always going to come back and destroy the Chronicoms.

Time travel