How on earth do I know which is the best food to give my puppy
Any advice welcome

Always listen to the breeder's advice. Did you not get a supply of the food the pup has been used to? Most breeders will give 3-4 days worth of food at the very least. It's never a good idea to switch abruptly so a change from one brand/one type to another needs to be done gradually, and a good breeder who has years experience of feeding pups and growing dogs of their breed will definitely be the best person to advice.

I've got three weeks before I get her and yes I do get some with her and it's royal canin but when I googled top ten foods it's not there so I was just wondering

I don't think you can go off Google as it depends very much on who is sponsoring the google advert.
As Goldmali said I would be guided by the breeder. Royal Canin is a very good food, all my dogs are on it and have lived long and happy healthy lives well into their teens.
I reared a litter on it in 2009 and they are all still on the same food, non have gone off the food when they got home. My dogs have been shown very successfully and have lovely glossy coats, fresh breath and nice firm stools.
If you do decide to change the puppies food you should do it very gradually over a period of weeks so that he/she does not get an upset tummy.
I would also ask your breeder about the choice of food and why they chose it specifically, some breeds have special dietary needs that the breeder may have taken into account.
Good luck with your new puppy.

and what suits some doesn't suit others.

I have regularly won Royal Canin food as they sponsor my breed club shows, but the only way ti doesn't make my dogs loose is to feed no more than 25% of it with their usual food, even introducing it gradually they cannot have it on it's own without getting sticky cow pat poos.

Would say the best food for at least the first 12 weeks it the one the breeder fed then if you think there is a good reason to change do it over at least 2 more weeks. I find it helpful to take a large bottle with you when you collect the pup and ask the breeder for some of the water the pup is used to. Since I started doing that I have never had a pup get the runs but before they always did, again as it starts to run out start to add your own water so the pup becomes used to it.

Yes I have found the s\me and ask the new owners to bring a bottle for water.

Both good points Brainless and Nova water from different areas can be quite different.
To be honest I think it is the change of diet that causes the upset tums I think. If a dog has been reared on one type of food it may not have had some ingredients in another before and this can cause an upset.
Hence why it is important to introduce different types of food in very small amounts first and increase gradually.
Having had alergic reactions myself I can say it is not pleasant, a baby puppy at 8 weeks in new surroundings and away from mum and their litter mates must find it traumatic to have an upset, as they can not tell you if they have stomach cramps.

Well one of my puppies was reared on bakers complete,she was healthy enough,but I changed her to a raw diet asap.I know its not for everyone,but,after years of trying to find the"best " food for my precious dogs,I did some research,and am now happy that Im feeding the best diet I can. Good luck!

As others have said, stick with what the Breeder has fed. They've probably put a huge amount of thought into the food they're giving their pups (OK, I don't feed RC but plenty do) and if you start chopping and changing as soon as you get pup home then you can guarantee runs. Besides food changes, and water (pah, I provide the plastic bottles!!) you have to take into account the HUGE changes the pup experiences from leaving mum and siblings to a totally different environment. The only time, I think, I would change from Breeder feed quite quickly is when fed Bakers :-O ... but, I'd still phase it out over a 2 week period.

If pup is doing well on RC then for goodness sake leave it on it :-D

>If pup is doing well on RC then for goodness sake leave it on it :-D

Ditto!

According to us, Eggs are a great and main source of very digestible protein, riboflavin, and selenium. For some dogs that are prone to digestive upset, eggs can give them a little protein boost. Make sure to use cooked whole egg, as raw egg whites can cause biotin deficiency. If you do a lot of training with your dog, consider taking cooked eggs to your next class as training treats. You may feed some eggs and some fresh and neat and clean flesh.

you can feed raw eggs, they do not have to be cooked as long as you feed the white and yolk together there will not be any problem with biotin deficiency