Is it possible to run the job only when a specific file changes?

You could set job level outputs in a previous job A. Use git command to check whether file changed during the workflow run. And then if file changed , you could set an output variable to true using ```
::set-output command.
Also please add needs : [ jobA ] in next jobs , add job if conditional, if the output variable is true then run these jobs.
There is the syntax for jobs.<jobs_id>.outputs .

Read full topic