Is there a way to make that so outside floorings won't connect with each other ? >https://stardewvalleywiki.com/mediawiki/images/6/6b/Weathered_Floor_Tile.png Like how they connect with each other in the picture is there way to stop that?
If you don't place them right next to each other, or vary which flooring you use, they won't do that. Otherwise no.