Hi dolphin, not a bad effort, just a couple notes on your Navmesh. The whol mesh should be one piece so the yellow line should not cross a section of pathing but only be on the outer edge. In your 3rd image you have a seam where two yellow lines are placed side by side, this will block the pathing there, it's a broken path. Adjust your nodes to get that yellow line along just the edges.
Also, you need to path around he bar stools, not under them. Otherwise character will continually be running into the stools thinking its a clear path
Just a couple tweaks and you can head to Lesson #3