What you are asking now, although not exactly simple, is far easier that what you originally asked to do. A lot of that has to do with Word jargon. "Template" has a specific meaning in Word jargon that is probably not what you meant. You were talking about the look or layout of the page.

How can I get a different header/footer on the second page?
I have several tutorials on letterhead and samples at Tutorials.

The key is the header/footer area and the controls for them. You can have different headers/footers on the first page than in the rest of the document so you put your material for the first page in the first-page header and that for continuation pages in the plain "header." You can use Frames or Textboxes in the left or right margin on the first page to simulate different margins if needed. This is not completely successful but works for most purposes. These can hold letterhead material or can simply move first-page text out of the way for a pre-printed letterhead.

There's much more about headers and footers in the page I linked to earlier.

For more about templates, see Templates in Microsoft Word.

I would, again urge you to start with the Shauno Kelly articles. They will save you a lot of time if you use Word much.