Time for action — moving the boat in sync with the oars
When you row, you dip the oar in the water and push the boat forward using the oar as a lever. The boat coasts while you are moving the oars back. You are going to create a marker to track that motion. When the oar is in the water, the marker will give you a location for the oar tip. When the oar is out of the water, the width of the marker will show you how far to move the boat while it's coasting:
Press Numpad 3 to get the Side view. Make sure you are on frame 0. Use the Current Editor Type button in the lower left corner of Graph Editor to change Graph Editor to Timeline.
Move your cursor below the boat. PressLMB.
Deselect all the objects, and make a cube. Move the cube so the left corner is just below the blade of the oar as shown in the next screenshot.
Select the boat and make a location keyframe. Do not make a keyframe for the cube.
Move the time to frame 26.
Select the boat and move it in Y so that the oar lines up over the left...
