The paving stones are about 10cm high, the curb stones about 25cm high.
So you are stating
a height that you want to cut. Is the stone wider in the other direction?
Ideally, the saw blade should go completely through the stone. Cutting from 2 sides is possible but significantly more complicated and requires more practice.
You can also score the stone and separate (break) it with a chisel. However, this requires experience. I tried it with a chisel specifically bought for this purpose – without experience – and sometimes it worked, sometimes the result was quite uneven...
It is also important how you can hold the stone to be cut. If the whole piece is small, it becomes difficult.
In any case, such a project is doable for amateurs but definitely a challenge.