I opened photos library on my mac and it doesn't have all my photos like the photos app does but now the photos app won’t open it only opens the new photo library

Try the following: Hold down the options key ⌥ while launching Photos. Keep holding down ⌥ firmly, until the dialog to choose a library appears, then release the key. Look at the list of libraries shown in the dialog. If there are more than one library shown, select them all in turn to find the library with all your pictures.