There are two types of websites when we talk about pages, a single-page website or landing page, or a multi-page or brochure website. Which you should have very much depends on your requirements, and what you are expecting from your website.
Benefits of a single-page website
A single-page website provides you the benefit of having all of your information in one place without the need to navigate to different pages. This is good for UX and UI because it is stated that your users should be able to get the information that they are looking for in as few clicks as possible.
Single-page websites can be nicer on the eye, just because of their simplicity. If the main aim of your website is to get somebody to contact you, a single-page website is probably just what you need.
It is important to convey your message and get the main information you want people to get from your website upon the first screen view. Although screens come in a variety of sizes and shapes, you can still effectively put across what you want your website to do for you as soon as the website loads. This is something that is beneficial for both types of websites, but more so for single-page websites, where the information you are providing is thin.
For example, if you want somebody to contact you, this should be in the top section of your website. Or apply an automatic scroll to the Contact Form, eliminating the need for them to manually scroll down the whole of your website, just to contact you.
A single-page website does not demand heavy amounts of content. Allowing a quick turnaround of development.
Benefits of a multi-page website
Multi-page websites are very useful for larger companies that are selling products or want to give much more in-depth information to their user base.
An E-commerce website should nearly always be a multi-page website. Users want to know who they are buying from, is the payment gateway secure, what is the returns policy, etc. multiple pages allow users to find out this information easily.
Multi-page websites may also suit corporate companies that have a much broader message to put across, or perhaps a selection of divisions – any company with a lot of information to present is much better off doing this over multiple pages.
Multiple pages can also have a benefit for SEO. The more pages you have on your website hitting keywords, the better your Google ranking.
Your requirements decide your internet destiny.