Trouble figuring out Pullover pattern from a Tiktok video

Hi!! Usually i do not struggle figuring such things out but lately i have been burnt out and need a proper crochet project to get my life together.
I really want to make this cute asf pullover i saw on pinterest (from tiktok), but i am having trouble figuring out the structure.

Part 1 has 12 squares joined together.

https://pin.it/2AEyvNzpM

Part 2 has the sleeves.

https://pin.it/2AEyvNzpM

Part 3 has how she puts it all together - this is where my trouble begins :(

Do i make 2 separate 12 squared panels OR do i not join the entire panel the way it's shown in part 1 leaving space for sleeves to be joined?

https://pin.it/7zAjHAoFD