Multi partition problems?

[longpanda]

You can refer to  https://www.ventoy.net/en/doc_disk_layout.html

With Ventoy-1.0.14 you can install Ventoy to your USB and reserve some space.
For example, You can reserve 128GB, and create a part3 with the 128GB reserved space after install.
So finaly the USB will have 3 partitions:
part1: 128GB-32MB
part2: 32MB
part3: 128GB

You can format part3 with NTFS and use it as you want.