Ibook G3 display issues

Hello Im new to this website also this is my 1st apple mac
When I cut the laptop on sometimes it loads up fine then the screen turns black or white
or it will load up fine and then if i touch it the screen freezes up or goes black
I would like to know is there anyway I can fix this on my own the mac was giving to me by a friend who had gotten it from school 3yrs ago so theres nuffin apple can do for me because i dont have the correct info about purchase so here i am lol looking for a soulotion online before i spend money on getting it fixed i did see something about logic board and some kinda shimmy anyway please help if u can thanx