Because your second page is numbered 2. That there is no number on the first page is irrelevant. You can tell Word to start numbering at 0 or you can insert a section break and tell Word to restart numbering at 1.



See Numbering Front Matter by Suzanne Barnhill, MVP.

I know that. I don't want it to start at 2 I want it to start at 1. That is just silly.
Different first page should make the next page page 1.

Do you want to know how to do it, or just to gripe?
Did you look at the link I provided? It gives pretty much step by step.

Different First Page is a header/footer setting saying that in this section, you want a different header and footer on the first page of the section than on other pages. This setting has nothing directly to do with page numbering. It only has to do with what is in the header and footer.

It doesn't seem silly to me. Many documents with a letterhead first page start the first page as page 1, even if not labeled. I would think that's the default in usage. Otherwise, depending on what's on your first page, creating a Section Break/Next Page would give you a fresh start. For our docs, we frequently have cover page, letter on letterhead, then page 2 if needed of letter as ii, table of contents as iii-iv, then restart numbering at 1 for the main document. We only use the Different First Page on the letterhead part; everything else is devised with section breaks.

A section break is unneeded for this requirement. Adding unneeded section breaks makes for more confusion and harder editing.