Correct me if I’m wrong, but my understanding is a lot of the theological beliefs about the Antichrist/antichrists evolved much later in time as interpretation of biblical scripture, and are not something that is explicitly stated by biblical authors (see https://en.wikipedia.org/wiki/References_to_the_Antichrist_i... for a quick summary).

I was raised in an evangelical religious environment with strong premillennial dispensationalist beliefs. It wasn’t until I later took theology classes at university that I discovered those beliefs I was taught as a child aren’t universal among christians, or even strongly supported by biblical scholars.