How we can send email notification reminder to the VM owner sate that your VM Snapshot is going to expire after 2 days in VRA .
By far the easiest way is to use the SovLabs Snapshot module which allows you to set a snapshot lifespan, reminder periods, exclusions for certain VMs, and a lot more.
Any other way to do via VRO ?
Probably. But it's a lot of work and not at all easy.