Peach tree pruning and fruiting advice, please.

I used some T&M vouchers to buy myself a dwarf, standard peach tree.

What arrived is this:-


The stem is much, much shorter than I was expecting and also you can, hopefully, see that it is pretty flat. My first thought was that I'd been sent and espalier trained one.

My second the was about T&M and unprintable (I've got two fig trees, one is a replacement for the first one and neither of them are what I ordered and the replacement one was three months later than it should have been as they forgot me!)

My third one was I'll ask the Vine.

So first question:- Should I grow it as an espalier (rather not) or should I try and prune it into more of a ball?

Second question: I assume I need to take out the three "little branches" you can see in the above photo and then prune a few of the others to buds that will grow into the space I want filling.

Finally, it is covered in flowers (it is in the tunnel which is due to be its home). I am fleecing it up at night as we are (finally) down to 0C at night but should I let any of these set fruit and if so how many, please? Finally (part 2) what if any feeding should it have?

Thanks in advance people.

PS The vouchers were because they messed up last year's plant order - that has just started arriving!