Yes you can call Him God but the preferred way for Him to be called is Allah.
Should I say Allah or God?
Allah is Arabic word and GOd is English word. Muslims prefer to use Allah because Christians also consider Jesus as God.
How is Allah all powerful?
Quality Meaning
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Omnipotence All powerful
Transcendence Beyond the universe
How Allah shows His omnipotence?
Omnipotence of Allah means that: He can do whatever He wills. He has absolute control over everything he has created. He does not need help of anyone or anything to implement His order.
What word means Allah is all powerful?
Omnipotence means all-powerful. Monotheistic theologians regard God as having supreme power.