R1(config)# router eigrp 1(autonomous system number)   -- it will enable eigrp process on a router 

                 network  10.0.0.0  -- advertise all directly connected networks to a router one by one this is just a example.

                 network 20.1.1.0 0.0.0.3(wildcard mask)  - it will enable eigrp on  only specific interfaces like 20.1.1.1  and 20.1.1.2

                 exit

To see on which interfaces eigrp is enabled  : show ip eigrp interfaces 

To see neighbour table in eigrp  : show ip eigrp neighbors

To see Routing Table  : show ip route eigrp 

To se Topology Table in Eigrp  : show ip eigrp topology

To see Topology all-links table  :   show ip eigrp topology all-links