Hi
It's quite difficult to give a template without knowing all details of what you're trying to achieve.
To do a simple BGP peering, the config will looks like:
router bgp xxxx --> your AS number (private AS any number between 64512 and 65534)
bgp router-id x.x.x.x --> Usually it's a loopback address used as router-id
neighbor x.x.x.x remote-as xxx --> Info given by your WAN provider (IP of the WAN router and their AS)
After that, lots more option but with this config you'll be able to build up a BGP peering and learn routes from your WAN provider.
If you're using VRFs, you have to configure the right address-family.
Thanks
Francesco
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