You can use gparted on your mint live session to resize the windows partition to minimal size, leaving the biggest empty space possible. Leave 500mo 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.