" is this god you are referring to the same one that all these Islamics worship? "
Absolutely ! The YHWH of the Israelites, the jews, Christians and of Islam is the SAME god !
And like all gods, does not exist, and never has, all gods were made up by men.
This particular god is a stark example of that, as we know exactly in History when he was made up, we know which peoples did so, and when he was introduced to the Israelites by those peoples. *
Eventually after a few Centuries he came to be viewed as the only god who should be worshipped.
So , the Thread Title should be "Why worship a god that does not exist ? "
* See the Book "The Early History of God" by Professor Mark. S. Smith.