Hiya,
Answer the simple question first:
You have 2,044,000GiB free
But ... that is just "raw" (normal) free space and doesn't account for anything like RAID levels, set size of volumes, reserved snapshot space for volumes, growth increments of CPGs etc.
Next .. a CPG isn't a container that has your volumes are in, it's not like a pool that you give disk space too, a CPG is just a template to say how you would like your volumes to be configured, so the space you see listed against the CPG is just the amount of space volumes are using that are using that CPGs template.
Working out how much space you really have left is awkward .. you basically have to guess!
It's a painful thing of a the 3PAR, the second picture you have shows the 3PARs guess/estimate as to how much usable space it would get if that (only only that) CPG was used for future volumes : 1,695,000GiB.
I personally like to work on the provisioned size of the volumes allocated to hosts (the size of how much each volume could potentially be if fully used).
I know how much "normal" space I have for volumes on each physical disks (either from the GUI with that first picture you have showing "Free:" or from CLI with "showpd -c" and looking at the total of the free normal chunklets column.
So long as my provisioned space is less than my normal space I'm happy, if I over provision that is me gambling no hosts go nuts and try to fully use all the space in their volumes. I'm an old school storage admin so over provisioning feels wrong to me
Hope that helps.