Computer problems missing start button and icons?

Please help, was trying to figure out how to get a csreen to be able to type a report and then print it, still do not know how, and then computer start button and icons and red x disappear, Turni it on it is there then when i clikc on anything it disappears again and have toi turn it off to get the start icons and red x please ehlp me i am beginner and almost in tears, have report due tomorro.