To bill repairs that were already entered jobs via the repair screen. These would be referred to as Un-billed Jobs or Loose Jobs. This is more common for wholesale repair jobs.
[note that for repairs done for retail customers it is suggested to enter repairs *via* the sales screen. That way, they are always attached to a sales ticket and so the billing step isn't needed.]
To retroactively link them to a sales ticket, create a sales ticket as usual and then choose Options, Repair Billing from within the Sku line
From the top of the sales screen.
And that will pop up the Job Billing screen where you can select one or more (Unbilled) jobs to be added to this sales ticket.
Note that each job that is billed will need a billing Sku number.
If you added that Sku in the repair screen then you will not be required to select it when you bill it.
But if a Sku was not added to the job, the billing step will require one.
Some repair billing Sku numbers are added to VJS initially, but you will likely need to make your own "menu" of repair billing Sku's.