If I need 5m by 2m for my stairs can I buy 5m round and turn it round for length instead on a plain carpet
I think it would look bad, if you are interested, contact me and I will come and see the work?
No, to make your carpet last you carpet will need to be verticaly going up the stairs. And not across the stairs.
Yes on plain carpet this is fine you can fit it either way on stairs.
When fitting stairs you want the pile to run up the stairs so the carpet can only be cut in way way to get this finish, so in short you can but will have lots of waste.