Hello ManivelR
Yes, it requires it's own license in addition to ESXi - based on per-CPU, per-VM or per-CCU
Which features are available in each licensing edition can be found here:
Do not there were changes from the 6.0 licensing if you are not going ESXi 6.5/6.7
https://www.vmware.com/files/pdf/products/vsan/vmware-vsan-62-licensing-guide.pdf
Obviously make sure you have (or can acquire) controllers, SSDs and HDDs/SSDs components that are supported for the type of vSAN implementation you are considering as using random/unsupported hardware will likely result in a bad time:
https://www.vmware.com/resources/compatibility/search.php?deviceCategory=vsan
Bob