parted and gparted come with all Ubuntu flavour install iso files, so you have them already. Disks come with some on the iso files.
You can mount the partitions one after another, but you can also mount them at the same time (but of course to different mount points).
For example: devices 'sda3 & sda6'
1. create mount points
2. mount each device
sudo mkdir /mnt/sda3
sudo mkdir /mnt/sda6
If the mounting is successful, you can browse to the mount point with a file browser or use terminal window commands. Remember that you should go to the mount points
sudo mount /dev/sda3 /mnt/sda3
sudo mount /dev/sda6 /mnt/sda6
/mnt/sda3 and /mnt/sda6
in order to see directories and files. So this is a critical step and depends on the way Windows was shut down (hibernated or a complete shutdown).
(If this is successful, you should also be able to copy files to another drive, where you have also mounted a partition, and where you have write access. You might need to copy with superuser privileges in order to perform the copying. But that is the next step.)
Edit: You can run the command
and post the output after trying to mount the devices