In fact from the beginning I tried so but I can not understand why it does not work or where I sin: in the image reported I try to make the two sides coincide but the flange does not arrive at the end of the sheet below.part change and use other axieme geometries to draw the sketch and flange function
functions and sketches must be done with a design logic and if this logic turns out to be wrong it starts from scratch.here I do but it doesn't give me the chance to use the drilling command, I don't understand where I miss it as it should also be quite simple.Obviously so is not possible. try to put yourself normal at the sketch and think how it can extend to where you would like... You should draw reference sketches so as to project the line up to the vertical edge and as a whole you must first build planes that coincide with that of the other side.
functions and sketches must be done with a design logic and if this logic turns out to be wrong it starts from scratch.
make a nice sketch in the shape of l on the plane perpendicular to what you work now and you're fine