I’ve been told Melchisedek is Jesus because Melchisedek is referred to the King of (Salem) peace in the Bible.?

First of all, Melchizedek is Christ. Christ wasn't born when Abraham was alive. Melchizedek has no genealogy as he existed with the Most High from the beginning. The promise made to Abraham was that the savior would come out of his line and that did happen with the birth of Christ and he came in the flesh according to the law.