I believe I'm on the right track, but have stumble across something with advertising BGP prefixes to neighbors. I am wonder how if I have a single ASN with multiple prefixes (126.96.36.199/24 and 188.8.131.52/24) with multiple upstream ISPs. How do I send BGP attributes to these upstreams to influence how ingress traffic would go to which router. See picture.
As you can see this is a GNS3 lab I put together. I have an ASN#99 with 2(two) prefixes (184.108.40.206/24 and 220.127.116.11/24). I also have two ISP neighboring routers. Tier3-1 and Tier3-2. I am trying to get from Tier1's perspective, the best path for 18.104.22.168/24 prefix is through Tier3-1 and the best paht for prefix 22.214.171.124/24 prefix is through Tier3-2.
Keep in mind, I cannot touch Tier3-1 or Tier3-2.
This is probably something simple I am missing. Appreciate everyones help.