Monitor wont work

[hobby_guy]

hi my monitor looks really and computer wont adjust by it self but it wont let me do it by my self ether its saying the resolution and color depth are currently set to very low level and i go to Control Panel and to appearance and themes then to Change the screen resolution i pick Settings tab and where it say Screen resolution only has set in less 640 by 480 pixels and where it say Color quality has Lowest [4 bit] and wont let me pick another option. I also try Advanced but it didn't work.
Well hope you guys could help me with this problem...