There is a way to take off from the first grid to the n grid.

Imagine that the last jump is one or two squares.

If the jump is a grid, the previous method of jumping from the first grid to the n- 1 grid is assumed to be-1.

If you jump two squares, the way to jump from the first square to n-2 squares is An-2.

Then An = An- 1+An-2.

Obviously A2 = 1, A3 = 2.

Do a simple calculation

1,2,3,5,8, 13,2 1,34,55……

A8 = 2 1

That's 2 1 method.