It's like this, an analogy:
My bike is made up of many parts - frame, handlebars, wheels, chain etc
let's say it has 20 parts - I still have 1 bike not 20 bikes.
And I can't ride my bike to the shop with only the frame.

So christians believe in ONE god not 3 different gods making up one god. god is god and he/she/it is one, but is omnipotent ie can be everywhere at the same time.
(of course I don't believe that for one moment but that's a different topic)

Hope that clears that up.

Peace

"Deaths in the Bible. God - 2,270,365
not including the victims of Noah's flood, Sodom and Gomorrah, or the
many plagues, famines, fiery serpents, etc because no specific numbers
were given. Satan - 10."