Hi and welcome from Ceredigion!
I would recommend extensive reading about livestock/animal welfare, Tim tynes smallholding book is excellent. I would also recommend rare breed sales and talking to the breeders, maybe arrange farm visits and such, get to know the animals and see them in their working clothes. This will not only help you decide on what breed you want but will also give an insight into how they're kept/managed and you will be able to make friends with the breeders who, hopefully, will be able to give advice in the future. Most societies have open days and such. You could also go on Rosemary's and Dan's smallholding courses, I hear they're excellent
all the best and please don't be afraid of asking anything you need to know, asking is learning!
All the best
WBF