Two nodes provide you HA architecture if you are running all services on all nodes. (You can weblogic admin server only one node). If one node goes down then your services still run on other node.
But take into consideration few things.
1. Configure Load Balancer, so that the LB directs to any one alive node in case of node crash
2. Configure to run all services on both the nodes
For concurrent managers, you can configure PCP
How to Setup and Test Failover of PCP on Non-RAC Environments. (Doc ID 743716.1)
Concurrent Processing - How To Setup Parallel Concurrent Processing Using Shared APPL_TOP for RAC Environment (Doc ID 278816.1)
If you are talking about DR then please see
Business Continuity for Oracle E-Business Suite Release 12.2 Using Oracle 12c (220.127.116.11) Physical Standby Database (Doc ID 1963472.1)
Useful E-Business Suite 12.2 Documents (Doc ID 1585889.1)
We can have weblogic only on one node?. This will not be a HA Architecture. What should be done if can have weblogic on both node in Non RAC environment.
Admin server cannot be run in Active-Active mode. For Admin server HA please see section 6.3 in
Configuring Oracle E-Business Suite Release 12.x Using Logical Host Names (Doc ID 1968231.1)