Hi there,
the GenerateBlocks plugin has responsive layouts for Desktop / Tablet / Mobile.
You will see three separate tabs for each in the Settings sidebar when you select a block.
If you select a Grid Column block, and switch to Tablet you can set the columns to a different width eg. 50% / 50% / 100%.
For reference:
https://docs.generateblocks.com/article/container-overview/#grid-item
For the vertical spacing on the Tablet and Mobile. You will need to select the Grid Container ( the block that contains the columns ):
https://docs.generateblocks.com/article/grid-overview/#editing-our-grid-block
Under its layout you will see an option for Vertical Gap.
Again select the Tablet view and add a vertical gap, then repeat this for Mobile.