Always worth checking the profile posts from time to time
here right side. Found it by accident
I would probably start with Red Blob Games due his interactive graphics. The A* post builds up from the easiest one to a full A*. While the code is python(?), it's still easy to understand. Sure, we can't copy that, but it's about the algorithm.
RefresherTowel is nice afterwards, when the algorithm is more clear. But thats me and I'm a little paranoid and somehow assum, people would just copy&paste code. No offense
The question is, do you need A* or is Dijkstra, maybe even FloodField/Breadth First Search enough. All these algorithms are also just the start for pathing. They make a useable grid. The pathing itself needs still work. Each Cell? Waypoints? For this, Red Blob Games is your source again.
But I'm sure you'll figure it out what you need.
happy coding!