As a frame-challenge, try considering the problem the other way around. Work out how far you want to ride in an average day and check what is that distance away on your route. Say 100 km or ~6 hours casual riding. But any steep climbs could halve the daily distance, or you might want a rest/easy day. Build tourist/rest days into your plan too.
Presumably you want to be at the destination within some amount of time, perhaps your visa has an expiry, or there's a flight to catch.
Now, once you have an idea of your overnight stop in a towns/village/city, then its more of a "where's a good place to stay in Dusseldorf with bike parking ?"
Your lunch stop might be better to be spontaneous - every town will have something, as long as you arrive around local-lunchtime then something will be selling food.
Depending on where in the world you are, there will be Cycling Guides, either in paper form or on the web. Though consider the post C19 world and everything may be out of date.
On the off-chance you don't find something, always have emergency food/water on the bike. A couple gels and a bar can be enough to get you to your dinner stop, and then refuel/rest.