Vercel provides tools and services for developing, previewing, deploying, optimizing, and hosting scalable Jamstack websites. I have no preference for Vercel over alternatives such as netlify; I just happen to have caught some Vercel marketing recently.
Vercel focuses on both front-end developer productivity and solution performance including a global edge network. Jamstack solutions hosted with Vercel can retrieve content from any headless CMS or other repository and integrate with any external system such as search, commerce, and otherwise.
Using Next.js or any Vercel-specific technologies appears to me as a form of vendor lock-in that could complicate moving to an alternate hosting provider. I guess React is already a bit of a lock-in, and therefore React server components could be acceptable. I plan to use ASP.NET Razor Pages to generate the HTML.
The easiest way to get started with Vercel may be to deploy a completely static site that does not depend on any CMS. Such a solution might use a static site generation tool to get files into something like GitHub for deployment to Vercel, which requires a GitHub account and a Vercel account.
Log in to GitHub and create a repository, which (unless configured otherwise) represents the document root of a static website. You can commit any files in this directory or start with something really simple, such as an index.html file that contains only the following:
Log into Vercel to deploy this GitHub repository as a website. On the Overview tab, click Create a New Project. Choose to Import Git Repository and select the github account and repository. When Vercel prompts to Create a Team, click Skip, then Deploy. The deployment process takes a moment, then Vercel shows a preview of the home page of the new website, which you can click to see the URLs that Vercel associates with the site.