The tile you just drew shows 3 roads coming out of a village. You place it next to an existing land tile. You must make sure that one of the new roads connects to the existing one.
You placed this tile. The road matches the road and the field matches the field. Well done!
After placing the land tile, you may place a meeple onto one of the tile’s roads. However, that is only allowed if the road is still unoccupied.
You placed a meeple onto the just-placed tile. Since the road was unoccupied, this was legal.
It is then the next player’s turn. They draw a land tile and add it to the board. The right-hand road coming into the village is already occupied. Your fellow player therefore cannot place a meeple onto it. They decide to place their meeple onto the other road on the just-placed tile instead.
The right hand road is already occupied. Blue , therefore decides to place their meeple onto the other road.
Whenever a road is finished at both ends, it counts as complete and triggers scoring (e.g. when a road ends in a village, city, or loops back onto itself).
When a road is complete, it is scored. In this example, your fellow player placed the tile that finished the road with your meeple on it.
Each tile the finished road is on is worth 1 point. Since this road is 3 tiles long, it is worth 3 points.
Now the scoring track comes into play. It tells you what score you need to reach with your remaining tiles. Each time you score, this goal gets closer.
Take the meeple that just scored you 3 points and return it to your supply. The blue meeple stays on the board, since it wasn’t involved with the scoring - it’s on a different region. That road isn’t finished yet, so you haven’t scored it yet.
Since your fellow player triggered the scoring, they move the scoring meeple 3 spaces forward on the scoring track. Finally, retrieve your meeple from the completed road, returning it to your supply.