This is a simple BIRD BGP Config with one Upstream and a single Prefix announcement. You can use and adapt this example for both v4 and v4.
You will need to replace the variables written in all caps with your ASNs, IPs etc..

Useful Bird commands:
For IPv6 on Bird 1.x use birdc6

birdc configure

Configure Bird with the config set in /etc/bird/bird.conf

birdc show proto

Show the Status of the BGP protocols

birdc show route export PROTONAME

Show all routes you export to a specific upstream/peer

Config Example:

router id YOUR-ROUTER-IP;

protocol device {
scan time 10;
}

protocol kernel {
export all;
scan time 15;
}

protocol static announcement {
import all;
route YOURPREFIX reject;
}

protocol bgp upstream
{
import filter {
accept;
};
export limit 10;
export filter {
if proto ="announcement" then accept;
};
local as YOUR-ASN;
source address ROUTER-IP;
graceful restart on;
neighbor UPSTREAM-IP as UPSTREAM-ASN;
}