Rose plant propagation at home fails despite repeated attempts

Though almost all videos show that rose plant propagation is simple, in reality some people are wasting their time and money trying to grow rose plants.
In metro cities, finding rose plants is not very easy, since the rose plant seller has stopped coming,
So to get a rose stem for the propagation experiment, roses with a long stem have to be purchased.
The rose plant seller on the main road is charging a very high price of Rs 20 per rose when the station seller is only charging Rs 10 per rose.
Despite using aloe vera and potato for propagation, the rose stems are becoming black very quickly.
There are no leaves or roots growing, the stem has to be discarded.