SQL alwayson on Active Cluster

Hello Experts

I have two SQL instances running on Windows, SQL cluster having 2 Node with shared storage( Active, Active type)

SQL sever version is running on SQL 2012 Enterprise edition

Can we implement Alwayson on this. Is it feasible then what are the complexities and steps.

Thanks

AlwaysON is just a marketing term and it can be thought as the same old FCI which uses shared storage, and at any point of time the SQL services are active on only one of the nodes.
Whereas is AOAG you have separate SQL instance running on both the nodes, where one is primary and the other node is secondary.
I assume you are thinking of implementing AG with FCI, if that is true then for AG's you need not have shared storage.
you can have independent storage on both the cluster nodes.

if you done want to disturb the current configuration, you can add a third node to the cluster ad make it as a secondary AG replica.