There is a very long YouTube video on dishwashers and how they work on YouTube.
https://youtu.be/jHP942Livy0?si=4oWfpbZP9fEMzCX4
Takeaways - run the tap until it’s hot before starting a load, use powdered détergeant, the cheapest kind is fine, use a little detergent for pre wash and if you don’t have a slot for pre wash, just sprinkle some powder in the tray. Use any type of rinse aid, clean the filters on the regular, and don’t use too much detergent, usually half the dispenser is sufficient. If you are getting soap residue it is because you are using too much detergent. The pods don’t allow you to change how much detergent is used, so it is super concentrated.