There are many Hebrew scrolls. But you are talking about the Torah, it is the first five books of The Bible.
Hebrew
The scroll inside the mezuzah is written in Hebrew.
Me'gee'la מגילה
scroll book = מגילה (megillá)
It could be Hebrew or Aramic.
Yes they are.
"SAY-fair TOH-rah" ... meaning "Torah book"
scroll = megilá (מגילה) The phrase "Torah scroll" is often translated as séfer Torah (ספר תורה)
It wasn't the Jews (plural) who wrote the first Torah, it was Moses, at God's dictation (Exodus 24:12, Deuteronomy 31:24). See also the Related Link.How did the first Torah-scroll come to be
For those who are not fluent in Hebrew, it is hard to read the Torah as the Torah scroll does not have nikkudot (pronunciation indicators).
That word does not mean anything in Arabic. Chumash in Hebrew refers to a book-copy of the Torah scroll.
When the Torah was read publicly at the time of the Temples, the person reading directly from the scroll would read the Hebrew and another person would translate to the commonly spoken language at the same time.