I'd like to install BT broadband, how can I check whether the house I'm renting has a BT internet access point (the landlord says it has a BT line, but I'm not sure that means it's broadband ready, and I'd like to have everything ready by the 8th of August)
It matters not what is already existing, you just need to order the service you require and whatever needs to be done to provide it will be done.
I think you are being very optimistic if you want service for the 8th August.
I can't find a way of asking whether it would be possible -- otherwise, I will just stay with my current internet provider.
It doesn't matter who your provider is, they will use the same line provided by Openreach unless your current provider is Virgin.