You can use gparted on your mint live session to resize the windows partition to minimal size, leaving the biggest empty space possible. Leave 500mg to the windows partition as a safety net.
Then during the install process :
choose manual install (not install on a full drive),
create an ext4 partition for the system (30 to 50 go) with a “/” mount point. It’s the system partition.
create a “swap” partition (size = your computer ram x 2). It’s the physical memory partition.
last create an ext4 partition (all remaining space) with a “/home” mount point. It’s the personal data partition.
Once the install completed you will be able to access your windows data from mint.
Back up your data before hand.
You can use gparted on your mint live session to resize the windows partition to minimal size, leaving the biggest empty space possible. Leave 500mg to the windows partition as a safety net.
Then during the install process :
Once the install completed you will be able to access your windows data from mint.