Also note in islam there are 5 pillars, beliving in tawheed(oneness of God), 5 times prayers, belief in angels and prophets, hajj, and ramadan(fasting). The entire belief system is different.
Also MOST IMPORTANTLY, there is no record of prophet muhammad staying in iraq or iran for days, or communicating with any zorostranians, he only went as a Merchant.
Also mention the hadith:
Umar ibn Khattab (ra) said: “As we were sitting one day before the Messenger of Allah (saw), a man suddenly appeared. He wore pure white clothes and his hair was dark black-yet there were no signs of travel on him, and none of us knew him.
He came and sat down in front of the Prophet (saw), placing his knees against his, and his hands on his thighs. He said, “O Muhammad! Tell me about Islam.”
The Messenger of Allah (saw) replied, “Islam is to bear witness that there is no god but God and that Muhammad is the Messenger of God; and to perform the prayer; pay zakat; fast Ramadan; and to perform Hajj to the House if you are able.”
The man said, “You have spoken the truth,” and we were surprised that he asked and then confirmed the answer.
Then, he asked, “Tell me about belief (iman).”
The Prophet (saw) replied, “It is to believe in Allah; His Angels; His Books; His Messengers; the Last Day; and in destiny-its good and bad.”
The man said, “You have spoken the truth. Now, tell me about spiritual excellence (ihsan).”
The Prophet (saw) replied, “It is to serve Allah as though you behold Him; and if you don’t behold him, (know that) He surely sees you.”
“Now, tell me of the Last Hour,” asked the man.
The Prophet (saw) replied, “The one asked knows no more of it than the one asking.”
“Then tell me about its signs,” said the man.
The Prophet (saw) replied, “That slave women give birth to their mistresses; and that you see barefoot, unclothed, beginning shepherds competing in the construction of tall buildings.” (The tower in Dubai!!)
Then the visitor left, and I waited a long time. Then the Prophet (saw) asked me, “Do you know, Umar, who the questioner was?”
I replied, “Allah and His Messenger know best.”
He said (saw), “It was Jibril. He came to you to teach you your religion.”
[Sahih Muslim]
Here is evidence that MULTIPLE people witnessed the Angel gabriel as in his human form, visiting prophet muhammad pbuh to tell the disciples and to tell them of there belief in islam.
So the notion of "islam copied other religions" is ABSOLUTLY FALSE. Since many witnessed angel gabriel (as) visiting prophet muhammad pbuh.
;)Umar ibn Khattab (ra) said: “As we were sitting one day before the Messenger of Allah (saw), a man suddenly appeared. He wore pure white clothes and his hair was dark black-yet there were no signs of travel on him, and none of us knew him.
He came and sat down in front of the Prophet (saw), placing his knees against his, and his hands on his thighs. He said, “O Muhammad! Tell me about Islam.”
The Messenger of Allah (saw) replied, “Islam is to bear witness that there is no god but God and that Muhammad is the Messenger of God; and to perform the prayer; pay zakat; fast Ramadan; and to perform Hajj to the House if you are able.”
The man said, “You have spoken the truth,” and we were surprised that he asked and then confirmed the answer.
Then, he asked, “Tell me about belief (iman).”
The Prophet (saw) replied, “It is to believe in Allah; His Angels; His Books; His Messengers; the Last Day; and in destiny-its good and bad.”
The man said, “You have spoken the truth. Now, tell me about spiritual excellence (ihsan).”
The Prophet (saw) replied, “It is to serve Allah as though you behold Him; and if you don’t behold him, (know that) He surely sees you.”
“Now, tell me of the Last Hour,” asked the man.
The Prophet (saw) replied, “The one asked knows no more of it than the one asking.”
“Then tell me about its signs,” said the man.
The Prophet (saw) replied, “That slave women give birth to their mistresses; and that you see barefoot, unclothed, beginning shepherds competing in the construction of tall buildings.” (The tower in Dubai!!)
Then the visitor left, and I waited a long time. Then the Prophet (saw) asked me, “Do you know, Umar, who the questioner was?”
I replied, “Allah and His Messenger know best.”
He said (saw), “It was Jibril. He came to you to teach you your religion.”
[Sahih Muslim]