Select the shown polygons and delete them.

In vertex mode, use Target Weld tool to weld the upper front vertices,of the hump, to the ones just below them.

Select the edge from the picture and use the chamfer tool to split it in 2 edges.

Don’t forget to adjust the vertices of the chamfered edge in the side view.

Target weld the vertex as shown in the next picture.

Select the side vertices and scale them along the X axis to narrow the hump.

Next, select the polygons of the body on top which we are going to make the cockpit. While in the polygon mode, use the Slice Plane tool to cut selected polygons, as shown in the next picture.

Select the edge from the picture and shift + move it upwards.

Select the side edges of the cockpit and shift + move the upwards. Then, move them along the X axis so they align with the sides of the hump.

Change to vertex mode and select the vertices where the hump and the sides of the cockpit meet and welt them together.

Go bask to edge mode and once again shift + move the edges upwards.

Again, do not forget to adjust the edges from the front view...

... and to adjust the vertices from the side view.