To be completely honest here, I have never heard of "Rebecca" as an Italian name. Period. Though if I am mistaken, it would be incorrect to pronounce it the way that the website listed. Correct:Reyh-Beyhk-Kah"Re" equals "Rey" basically, or otherwise "Reh," softly for both. Roll your "R." The "E" in "Be" is the same as "Re," being that it is spoken as "Bey," "Beh." Normally the "C"s would create an English "Ch," but since an "A" follows immediately after: Hard "K." Both "C"s must be pronounced. Most easily accomplished by adding extra emphasis on the letter before, in this case "E," and continue that slight lingering "E" throughout "CC." "Ca" equals "Kah."
Some people I know pronounce it RUB-E-KAH. My friend Rebecca told me that's how it's pronounced in her country, my mom pronounces it that way too, for some reason.
• https://en.wiktionary.org/wiki/Rebecca#Dutch (in English)
• https://nl.wiktionary.org/wiki/Rebecca (in Dutch)
• https://nl.forvo.com/search/Rebecca/nl/ (in Dutch)
• https://youtu.be/en5QMeLhceA (in Dutch; the name is said at 0:00 and 1:30)
Converted to IPA, it should be: /rə.'bɛ.ka:/ [noted -ed]