In the first container of that page ( the one with the grid inside it ) add a new Headline block above the grid.
Simplest way to do that is to select the Parent Grid Block, and from the Tool Bar 3 dot menu select Insert Before.
Select the new block and + Headline Block.
With the Headline Block selected, in Settings > Spacing toggle Inline Width and then give it some padding. Then add some Negative Top margin e.g -60px to pull it up over the container above it.
You can also change its background and text colors in the settings.