Only let info contained in 1 list column be typed into another lists column

[PEGJD]

My company uses a SharePoint list for requests for specific tasks to be done for thousands of existing jobs we have.  We have a dedicated excel sheet used to track that right now. I am trying to get that to be its own SharePoint list right now.  If I convince the big boss to switch, can I have the SharePoint form only allow one of those existing job numbers to be filled into a column?

The reason is we have a very complicated naming scheme for job numbers so people frequently add an additional 0 or 1 and it screws things up.  It would be amazing if this could be done as it would really cut down on wrong job requests.

[#2]

@PEGJD "can I have the SharePoint form only allow one of those existing job numbers to be filled into a column?" Yes, create a separate list with the unique job numbers in the Title column (and other details in other columns if you need that). Then in your main list have a lookup column so the user can only select one of the existing job numbers and can't add their own extra numbers.

Rob
Los Gallardos
Intranet, SharePoint and Power Platform Manager (and classic 1967 Morris Traveller driver)