I think people should have to be licenced too, & not only for pets. I'd thoroughly test people, then assess the conditions where the pet will live, & have snap inspections, too.
She sounds like a very smart dog, too.
I wonder if the RSPCA would help you with the vaccinations & getting her desexed, (If the Organization can't help)?
I think the training is an excellent idea. After a while, you can be taking her out & socializing her.
Watch it with those treats! & the food, because if she had not been sure of a meal, she might be eating as if no meal will be offered the next day, so better eat while the food lasts, no matter if she isn't hungry.
Long as she is very active, it may not seem a problem, but as she gets older, wanting heaps of food may be a difficult habit to manage. It may also have consequences , like any poor diet would for us.
Hugs to the lovely dog. Virtual hugs to you. (Yes, dogs & cats get real hugs! 😺)