I recently cut down all trees n bushes at the side of mum and dads house for me to lay turf down, its left big stumps that iv tried rotting but nothinks happened.Does any one know how to get rid of the stumps plz?

Its been about 3 months since i cut the bushes down so the ground has gone rock hard, whats will be the best way to to lay turf down. im only 18 so im still living at home so i aint that good at gardening. If any one can help plz do so. tar