Grid snapping/Autofill

Hi there, I’m currently designing a level and have encountered an issue. I am using multiples of a “floor” object in a square shape and am copy pasting and then manually moving the position after.

Each blue square (4x4 mini squares) is one object and I have been placing them one by one then manually moving them the specific distance from one another (200 in this case). I was wondering if there was an easier way to fill an area with these objects or perhaps snap them so they attach to the end of the object I am hovering over?

(My current method of filling an area by copy pasting and moving)

(Dragging a new object in - is there any way to snap this to an already placed object?)