Wrong. Jesus was and is the Jewish Messiah and He spoke Hebrew, which may have included Aramaic words, but it was still Hebrew --- not Aramaic. The name "Cephas" comes right out of the Hebrew [Strongs #3710 keph] and means a "hollow rock" --- which is hardly anything that one can or would want to build their house upon, much less a church. Thus if the RCC has built itself upon Peter as Cephas, it has been built upon a "hollow rock" --- not a solid one --- which explains its hollow foundation.
This may come as a surprise but before the Christian era, Aramaic had become the language of the Jews in Palestine. Jesus preached in Aramaic, and parts of the Old Testament and much of the rabbinical literature were written in that language. Christian Aramaic, usually called Syriac, also developed an extensive literature, especially from the 4th to 7th centuries.
Aramaic began to decline in the 7th century AD. Aramaic survives today in Eastern and Western dialects, mostly as the language of Christians living in a few scattered communities in Syria, Lebanon, Turkey, Iraq, and Iran.
Hebrew, dear friend, was reserved strictly for Synagogue services. At that time, Hebrew was the liturgical language.
BTW - I am truly blessed to be a member of a Maronite Catholic Church where, to this day, Aramaic - the language of Jesus - is retained for the Institution Narrative. It is as close as one comes to the Last Supper.
It can just as easily come from the Greek for "head" and the Aramaic for "rock", both of which (kephalaios and kepha) are similar to Cephas.