Looking for tips for Poland roadtrip!

Hello! Me and my partner will be doing a short roadtrip throughout Poland, from Wednesday to Sunday.
We will be visiting Katowice briefly, a day in Lodž , then Gdaňsk and Štetín.
I will be more than happy to get any tips for the trip – things to see, things to be vary of.
The thing I am most afraid of is the parking – we will be sleeping in our car. I found a website czaswlas.pl from which I chose the parking spots for night. Will those places be fine if we keep quiet, don’t leave any trash and leave early in the morning? Are there any more sites/maps like these?
Thank you dearly! Pic for attention 🙂