Hi @Mukil Vendhan
I use Report Builder. I can directly drag two tables to increase the distance between them, but it seems that it is not what you need.
Maybe you can try to put the first table in the rectangle, and the second table is put into another rectangle to control the blank space between them. For more details, you can refer to this link: ssrs-controlling-space-between-two-tablix.
Best regards,
Aniya