Frustrated by bureaucracy, I created a website that points to the exact formalities required by each country, for each migrant.
I moved to Spain last year and, while all my papers were in order, finding the exact legal papers that I needed to stay here wasn't all that simple. While only ONE route was the exact one I needed, several routes seemed right for my situation, all of which was only cleared out when I arrived to the migration office.
So, I created a website that works as a decision tree, asking you basic questions, step by step, in order to narrow down your profile and arrive at the exact formality required in each case, with official links included. It works for most countries, and in several languages.
It's free, and it does not collect personal data (the questions do not ask for personal data).
For safety reasons, I avoid clicking on URLs here on Reddit, so to make it safer for you, just google BorderChecklist and its probably the very first link (yes, the name of the site is Border Checklist).
Anyway, I hope this helps. Any suggestions are more than welcome!