Do you not already have a telephone line connected to your property ? Almost 100% of British houses have a telephone line these days, even if its not working at present. Are you perhaps changing from one provider of a telephone service to another ?
If you DO NOT have a working line connected to your house, than that would need to be installed, probably by a thin cable coming from the nearest telephone pole, or by a underground feed, if your house is more modern.
In either case, my experience as a BT Engineer of may years standing
( although retired now ! ) tells me that they whole process may take a while, as connections would need to be made in the local Telephone Exchange as well.
Let us know here on AB how you got on today !