Hi,
I want to utilize all three for read and write instead of just using one, so that it will load balance across all the three nodes thus enhancing read and write operations
There are 2 sides to this, one is which node your client application (curl in this case) will send the request to, then there is the execution of the query.
Regardless of which node receives the query, CrateDB will try to use all the resources of all nodes to complete the request as soon as possible, you can read about sharding and replicas, that is how CrateDB distributes data across the nodes.
Which node your client application sends the request to is still important so that if there are lots of clients the requests can be balanced and in case a node is not available another node can still be reached.
Ideally you would deploy what is called a load balancer, this is the same that you could use for any http web server. If you are looking for a simpler solution you could have all nodes on the same port but on different IP addresses and use DNS round-robin