Yes... i can help you.. silverton97...
1— get an external hard drive/SSD .. your iMac pro supports both USB-C and thunderbolt 3..
2-the drive should be roughly the same capacity/size as the one in your iMac pro.. either1,2 or 4 TB..
3-connect it to your imac pro while it’s turned off.
4- under Finder preferences make sure show external/removeable drives is turned on
using Disk Utility, format it ( the external drive) for Mac, as needed
5- turn on Time Machine app, which is built into the OS... after it’s turned on, point it to the external drive and DO A BACKUP.... backup everything... this will save your bacon... get the external drive, set up time machine and do it asap..
6- now you have Done a back up, do it and use it regularly, You can even schedule it to do it automatically once a week or once a month, whatever you like.
7-now that that important, basic and crucial thing is going and working
8-you can try something like data rescue 3 , Maybe disk warrior or tech tool pro to hopefully fix your hard drive enough, so that you can back your stuff up and you won’t be totally up the creek without a paddle. As for the failing hard drive itself, you would have to make an appointment with your local Genius bar , in your local Apple store and take it in for service. And Replacement of the SSD inside of it.You could also try finding a local AASP ( Apple authorized service provider) . Those are your options.
john b