it will be a self planned B and B type of tour.. . . local shop are recommending a Genesis tour de fer. . . . but are there better options? I want to get the bike early so I can . . . get used to riding a more laden bike especially up hills. Ive also started looking at route
If you are planning to do this B&B, you need not carry much stuff, so don't concern yourself with "riding a more laden bike", not until the last month or so before your end-to-end. Carrying close to what you plan to take (and how you plan to carry it) is more testing the carriage system and robustness, rather than fitness or bike handling. Of course how much you carry depends on your standards of sartorial elegance overnight and eating out.
The Genesis Tdf looks lovely (and another has mentioned the need to decide whether to go for flat or drop bars). But it's a lot of money, so you need to consider what other cycling you might do before and/or after an end-to-end. I recommend you get a (much) cheaper bike to discover how you feel about some of this stuff, and then, with that knowledge gained, get a bike (second hand, unless you are a must buy new person) for the end-to-end.
Normal brakes will be fine for this type of cycling. Discs are not needed (see comments on load below). On the other hand, discs will allow a wider tyre which might afford more comfort. Also you will not be riding at night so the generator hub is a significant additional expense: one you probably don't need. The chainset is 44-32-22. This is very much a touring triple, anticipating you carrying heavy loads and looking for some serious hills. See total weight comments below.
The wheels are both 36 spoke with good rims, which will mean good strong wheels, probably stronger than you need, but if you are 16+ stone then well worth having strong wheels. This bike is designed for the 4 panniers and rack bag brigade (carrying camping kit and and 30+kg). It needs to be strong for that, and discs give it stopping power. At 15kg plus, this is not a light bike, but it's steel.
As far as a route is concerned, loads of planning fun to be had by looking at the options and planning your own.
Here is a link to my post where I attempted to list the factors and questions to take into account / consider.
@robgul is an expert and will direct you to his wonderful website, as well as offering his comments, I hope. Join the Touring Cyclists Club.