Stucked with assigning additional ip blocks to opennebula kvm centos 7

Hello guys,
I just bought a server with following ip assignments when i ask my provider for additional ip configuration help they gave me the link to this tutorial https://www.unixmen.com/linux-basics-assign-multiple-ip-addresses-single-network-interface-card-centos-7/ as it was for multiple addresses in the same subnet I just google more and found this tutorial https://zubayr.github.io/virtual-ip-assignment/ and i did exactly as it say by creating 2 range file for each of the following assignments but it didn’t work.

IPv4 Assignment #1: xy3.208.x53.242/29 IPv4 Assignment #2: y4.9x.25.xx2/28

I can successfully configure the server with only one ip block with bridged networking but i need to know how to configure it with the additional ip block.

I really appreciate if you guys can provide me with a solution as soon as possible.

Thank you.