EIGRP is a routing protocol protocol proprietary to CISCO and is really easy to learn when compared to others. Please check the below video to see how to establish an EIGRP neighborship.
EIGRP protocol uses hello packets to establish neighborship. Once we define network statements on EIGRP running routers, hello packets are exchanged between them. Once K values are matched between them and they are coming under the same subnetwork, EIGRP neighborship will be formed.