The holder of the master franchise in UK doesn't sell any franchise to individuals... hence all Nando's in UK are owned and operated by Nando's UK.
However if you do own some prime properties which sees sufficient traffic volume they might be willing to enter into a deal with you on a profit sharing basis in exchange for lower or no rent.
Anyway franchise isn't the best way to start your first restaurant as it is very capital intensive and usually it is rare that you would be allowed to operate one by the master franchiser unless you have :-
1) Substantial capital
2) Sound business experience and being a landlord doesn't count.
3) Good knowledge in the restaurant or high volume catering businesses. Just because you know how to cook doesn't count either
Profits don't come easy either especially if you have to pay high rental rates for the premise as in addition to paying the franchise fee, you will need to renovate that premise to their standard (this can be once every 3-5 years) and you usually have to buy or lease their equipment as well, some of them are hugely expensive. Supplies, you can only buy it from them though usually wholesale prices aren't standard, depends on your volume and markups as a whole is controlled as prices need to fall in-line nationally. Then each time there is a sale you have to pay between 1-5% as royalty. Some franchise also comes with targets so you need to guarantee them a certain amount each month or else.
I looked into several franchises before in the end realized it is better to start your own, market it well and do it well than to rely on a franchise unless you already own the premise you're not going to make money out of it. If you're really interested in doing a franchise business especially if it is your first time going into it, then look for Domino's Pizza instead... significantly easier and far less labour intensive and you can also operate it very small premises. The other alternative though rather risky is to bring in an American eatery that isn't yet present in UK... if they are interested in expanding internationally then they usually are quite good about it.... looking into the possibility of bringing in 2 right now, though into Switzerland first and then into UK.