Wrong place

why are new items in the wrong place? i download something from the warehouse or make a new object and they end up out in space and not aligned with same plane of my exist model.

Can you share an example file that shows this?

It’s not unusual to find components in the 3D Warehouse that have their origins set at a long distance from the geometry. The origin is the insertion point when you bring the component into the model. Best practice is to download components from the warehouse into their own SketchUp file so you can check for problems like this and repair them before inserting into your project.