2002 Mazda Millenia Errors with car engine

I have the errors below, P1402, P1521, P0300, P1195, P0161. I Changed my engine and after changing the engine, I got the P1195 (Barometric pressure (EGR boost) sensor circuit malfunction), P0161, I also have been faced with P0161 and P1402. Of recent I noticed that my engine was not revving well so I scanned I got a P0300 error, I have changed the plugs, cleaned up the nozzles and still have same issue, I suspected the camshaft sensor and have requested that a mechanic check this and still same issue. The engine does not idle well.