Is SAT scores are enough to enter a university in US or Canada?

well im an advanced level student living in sri lanka , our examz are really hard and kinda hard to get thru only 20 000 wil p an exam frm abt 100 000 students , and only abt 800 students will be able to get into a uni here for engineering, so i have decided to SAT but i dunt knw much about american uni system, are SAT scores are enough to get into a uni or do i have to do other examz.