Hello,
I would recommend a free PDF developer's library for C# PDFFlow for your needs. You basically create PDF documents from scratch with it. It supports repeating headers, automatic page numeration, multi-page spread tables and many other layouting options.
It is lightweight and fully documented.
Also, many samples of business documents built using this library are located in a repo (PDF.Flow.Examples), I haven't seen that much from other PDF generating libraries. There are also how-to-build articles for each sample, which definitely might help you get going.
Your first PDF you can create with just a few lines of code:
var section = DocumentBuilder.New().AddSection();
section
.AddParagraph("Hello World!").SetFontColor(Color.Red)
.ToSection()
.InsertNewPage()
.AddParagraph("This is another page inserted")
.ToDocument().Build("Hello World.pdf");
As you can see, there is a method InsertNewPage() which can be called at any moment.
I hope, this is what you were looking for.
Also, this library automatically creates new page when current page is finished, so the content is continuing at the next page. This is very comfortable, so developer don't waste time for this.