for that height and length you will need without fail to get a structual
engineer to design your wall. If you know nothing about it then do not even
start. 10' high by 18' long is an enormous amount of weight. You will also
have a problem constructing it due to possible slip unless it is designed
properly.
Back to your original question about hollow concrete blocks then yoes in
principle what you have said is standard practise for smaller retaining
walls.