For driving motor you can build discrete H-bridge (which is general way to control DC motor rotation direction) or use some integrated bridge like L298, LMD18201 or similar. For buttons see any microcontroller related tutorial, this is the most basic thing ever. As for LCD, if is has HD44780 compatible controller (which i'm almost sure it has) you can find TONS of info and libraries too.
If i press key on keypad interfaced with 8051 then program jumps to defined label . Mean how can i program 8051 so that it compare the pressed key and if key is nt that i want them program control jumps to defined label.