What is the correct conduct?

Your answer is correct because, according to German traffic rules, trams always have priority over other vehicles except when special traffic signals indicate otherwise. This means you must yield to the tram first.

The tractor on the right is at a secondary road (indicated by the yield sign and the priority road sign you see ahead), so it does not have priority over you if you are on the priority road. Therefore, you do not have to let the tractor turn first.

In summary, always give way to the tram because it cannot swerve easily or stop quickly. That is why the correct behavior here is to let the tram pass first.