In the United States, when you are outbound for sea you would have red buoys (even numbered) on your port side(left) and green buoys on your starboard side (right). When returning fromsea you would have red buoys on your starboard (right) side (Remember " Red right return") and green buoys on your port side (left).
Keep the buoy on your port (left) side.
I think you should----Keep the buoy on your port (left) side.
port side(Left)
pass on port (left) side
You go inside that space that has the bouy and stay to the port-side of the bouy.
Keeping it on your port, passing it to starboard, will prevent your running aground.
When heading upstream green buoys should be on the left/port side of the boat . The opposite is true when traveling downstream.
Since this is a Green Lighted Buoy sighted while approaching a harbour,this is a Lateral port hand side mark, IALA region B. To keep this buoy on your port side while travelling upstream.
Do not pass between the buoy and the shore
If it's "red right returning", it's green left returning and green right (starboard) going. That is to say, you pass it to the left (port) as you return to port.
You should keep the buoy on your starboard side. The channel should be marked with green to port and red to starboard as you enter.
Keep the buoy on your right or starboard side.