Dual BGP connections advertising the same subnets

Hi,

I have two BGP connections (A & B) handed off, from a 3rd party, to my two Cisco Nexus switches (X & Y). The problem is they advertise the same subnets. Basic Diagram.

Question 1 -

How do I advertise these BGP routes to the rest of the WAN? (How do I redistribute them into OSPF)

Question 2 -

How do I prioritise A on the X side switch, and B on the Y side one, but still have both A and B available on both, for redundancy?