In my Mint 20.2 desktop I am low on space, memory. It looks like Timeshift for some reason is using 74GB of memory? Can I free this?

Also in Gparted I created space to the left of my Mint install, so 56 GB. I don't know how to expand my Linux partition into it. I tried G parted and Mint disk manger.

To the far left of my memory is Windows 10, that I little use and shrank down with Gparted.

I cannot visualize what you describe as space on the drive. You have mentioned both to the right and to the left of the mint partition may be free.

Gparted cannot modify a mounted partition under most circumstances.

I suggest you download the live image of gparted, boot to that, then modify the installed partitions as needed while they are not mounted. Gparted should be able to relocate & resize the partition into unallocated space on either size of the existing partition.

You will have to ensure the file system used allows resizing. I think that an xfs file system cannot be modified, but most others can. If your file system cannot be modified then you may need to do a full backup, alter the partition, then restore/clone back into the enlarged space. An ext4 file system can easily be altered.

How many backups is timeshift configured to keep?
I assume your saving the backups to a separate partition?
Is it configured for rsync or btrfs?
Are you using LVM?

As posted you can boot gparted live and move your existing partitions left to take up the free space and then enlarge whatever partition as desired but depends on the above questions.

It does seem to me that Timeshift is "getting carried away," but let us hope that Mint implements LVM = Logical Volume Management.

If so, then the various "logical 'mount points'" are no longer tied to "'disk partitions.'" Instead, they are tied to "storage pools" which are served by disk partitions but can now seamlessly extend into more than one of them.

I cannot recall if two years ago I used LVM when dual booting my drive. The left of the drive in disk management is Windows 10 then a free space then Mint to the right.

I will try again at Gparted from the live mint distro.

But there is only one Timeshift record from the day I got the warning, I may have to avoid risks and not use it and wipe the Timeshift record to clear space. How is it done? To clear 74 GB?

I think I will turn Timeshift off. It is RSYNC, and I can delete it.

Perhaps if I format the free space?

Look at the output of df. If you see /dev/mapper then you are using LVM.

If it is a separate partition then formatting will essentially wipe everything. As previously posted you can tweak the settings to only keep x number of backups.

On most distributions /usr uses about half of the space occupied by Linux. You can copy /usr to an empty partition. Change fstab to mount /usr on the new partition and reboot. After you reboot you can delete /usr on the original Linux partition and free up a fair bit of space.

Also if the new /usr partition is on a separate hard drive Linux will run faster due to overlapping I/O on the two drives.

While you have another filesystem mounted to /usr/, you don't have access to /usr/* on the / filesystem. /usr/* needs to be moved elsewhere (or copied and original deleted) before elsewhere gets mounted to /usr/ and the modified installation booted. Otherwise, no space on / is recovered by employing the additional filesystem.

I had one Timeshift record which I deleted and my disk manager shows I am back down to 41.7% use of my drive space.