- Select and delete these faces:
- Select and delete this vertex:
F2 allows you to select one edge of the hole, position the cursor inside the hole and then create the face with F. Select the left most edge of the hole, position the cursor to the right of it, and type F ten times. This is fewer key strokes than filling the individual holes.
- Select the 4 edges of the left hole and add a face with F:
Use F2 to fill the right hole.
The easiest way (at least to describe) to deal with the rest is:
select all of the edges surrounding the remaining hole and make an n-gon face:
- Finally, use the knife tool to subdivide the N-gon into six quad with three cuts:
You might want to edge slide vertices to smooth out the new lowest row of faces.
By the way, you have a similar but slightly different problem on the other side of the axe. If you deselect all and then use the Select menu to Select All by Trait -> Non-Manifold you'll find the problem: