Reworking a site plan usually starts with picking up something that's already there, a building, a parcel, a road, and moving or adjusting it.
Activate the Select Tool
Click the Select tool (icon looks like a hollow arrow cursor) in the drawing toolbar, or press V, to select and move whole geometries.
Select a geometry
With the select tool active, Click a geometry to select it.
Shift-click to select more than one.Click and drag over empty space to box-select everything inside it.
Press Esc to clear your selection, or Delete/Backspace (Cmd+Backspace on Mac) to delete the selected geometries.
Select All, Lasso, Toggle X-Ray Mode, and select by type or ID all live in the ••• menu's Select submenu.