When entering this intersection, do you have priority over the vehicle on the left?

Why?

The row of triangles marked P-13 shows where to stop if stopping is necessary to give way. You are entering from a minor approach, so you must let the vehicle from the left pass. Priority here is determined by the traffic signs and markings, not by the give-way-to-the-right rule.

§ 89 ust. 2 oraz § 5 ust. 5 rozporządzenia w sprawie znaków i sygnałów drogowych