You have to type
LOAD"*",8,1
and hit enter.
after the game loads you might also have to type
RUN
and hit enter.
You're best option is to learn to use a commodore 64. Old computers were a lot different from modern consoles. The operating systems of these machines was very complicated compared to today's machines, they mostly didn't do point-n-click, you have to type in commends to make it do things.