convert date and time to different format

Try this ...

=DATE(2000+MID(A1,FIND(" ",A1)-2,2),LEFT(A1,FIND("/",A1)-1),MID(A1,FIND("/",A1)+1,FIND(" ",A1)-4-FIND("/",A1)))
+MID(A1,FIND(" ",A1)+1,5)+0.5*(RIGHT(A1,2)="PM")