First off, greetings Ciara1127 and welcome to the forum.
If you want to read about the life our beloved prophet and messenger, Muhammad (may the peace, blessings, and salutations of God be on him), then a reliable biography, which is known in Arabic as Seerah, is a good place to start. There's a well renowned seerah called "The Sealed Nectar" by Safiurahman Mubarakpuri, (can be downloaded here: https://islamfuture.wordpress.com/20...f-the-prophet/
) and another called Muhammad: Man and Prophet by Adil Salahi, among others. That's a better way of reading about his life, as a complete account in chronological order; his early life, how he was bestowed Prophethood, the struggles he faced, and how he preached the same message as all the other prophets of God, and transformed a land of polytheism into a land of monotheism.
Yes, as a normal human being, for that to happen to anyone would initially be frightening and worrying. The seerah books will explain it in more detail, so please do read them.
Thank you for your love and concern for us. Believe it or not, we have an even greater concern for you.
I presume being a Christian, you believe that God begot a son (who was also actually god) and had him killed in a slow, painful, bloody, and torturous death to atone for your sins? And you believe he cried out, in effect to himself, "Why have you forsaken me?"
You see, we, as Muslims, believe in, love, respect and honour Jesus (peace be on him) and believe in him as he was; one of the noblest and purest of humanity to ever walk the earth, and one of the greatest messengers of Allah, sent to the Children of Israel. We do not reject him (as Jews do), nor do we deify him (as Christians do). Neither he, nor any other messenger, ever claimed divinity, or to be God's son. We believe he was born miraculously of the noble virgin Mary (peace be on her), and that he is the messiah. We do not however, believe that he died or was crucified. He'll return to earth near the end of time.
Let us discuss first what truly believing in one God means, and what central core message all the Prophets and Messengers of God preached.
Regarding God, we believe:
There is only One God. He alone should be worshipped.
He is our Creator, Sustainer, and Lord.
He does not beget, nor is He begotten.
He has no sons, daughters, spouses, siblings, parents, cousins, or relatives of any sort.
He is eternal and does not die.
He does not depend on anyone/anything yet we all depend on Him. He is free of all want and need.
There is nothing like Him.
He is all Hearing, all Seeing, all Knowing, all Powerful, Incomparable, the Creator of the Universe.
He did not/does not, become flesh, dwell in human or animal bodies, nor are there any incarnations of Him.
He is not mixed up in His creation in any way.
He is not composed of persons, nor a trinity.
There are no secondary, lesser, greater, equal, or multiple gods, nor any intermediaries. And no denying of God's existence either.
There are no sharers, associates, persons or parts whatsoever in His exclusive Divinity. Simply, He is One, in every sense.
As you can see, the concept is clear, simple, logical, makes sense, and befits the Majesty of God.