Mac os has a 1TB SSD but only sees 600GB

so if your fiddling with Disk Utility clobbered your drive, that is Backup good enough?

Could you start over and recover all your files from that?

if so, you can proceed to Disk Utility.

Select the existing MacOS Data Volume, then choose the Partition command.

expand the existing about 600 Gb into the additional free space.

This will re-organize the drive and allow it to expand into the Free Space that has already been vacated by removing the 400 GB Windows partition, according to your diskutil list posted earlier.

Partition a physical disk in Disk Utility on Mac - Apple Support

use the 'Enlarge a partition on a storage device' heading

NB> you are NOT adding a new partition -- that is not recommended. You want to Expand the size of your existing one.

what happens if you try to specify a larger size in the size box for the Monterey partition?

your diskutil list suggests the striped area has ALREADY been deleted, and the Monterey volume should be expandable into it.

One more reason to have a very recent trusted backup is that expanding/shrinking does not always go to plan, and the backup plan is to ERASE the drive, create a 1 TB Volume, re-install MacOS and restore your files from backup.

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in Disk Utility, use the little View menu to "show all devices".

choose the PHYSICAL device, usually at the top of the list and not indented, by its immutable manufacturer-given name.

if that says your Physical device is only 600, you have a MUCH bigger problem.

From exactly that screen (with the 1 TB Physical device selected) choose Partition, then follow the instructions in the article under the heading I mentioned.

the article should be available in your local language.

When you attempt to fiddle with disk partitioning, you risk making a mistake that causes Disk Utility do things that are unexpected.

¿what is the date of your most recent backup, and by what method?

Excellent!