You will need to add an air admittance valve under the cabinet to vent it.
Put the drain assembly onto the sink, add the flanged tailpiece. Then cut the 2" pipe at the appropriate height, glue a 2"x2"x1 1/2" sanitary tee on, then attach the trap to the side of the tee, and an air admittance valve to the top, as high as possible.
Lake County, Florida plumber
Springtime Plumbing Services