My partner makes over 3500 without a t4 but doesn't have a business. I know it falls under self employment income but how would I file it?

My partner is paid weekly at a salaried amount however no taxes are taken off and no t4a is recieved. What lines would I file his income under he only has one employer and a check is written out every week for the same amount but it is well over 3500 and did only that for the entire year. Which program would be the best fit as well?