I am afraid of a possible misunderstanding, but Cloudflare is not a hosting provider.
To install an SSL certificate which you bought from Namecheap, either to make your Website work, you would need to place your content (images, text, files, etc.) on a web server including your SSL certificate to have HTTPS (secured connection to your website), which is provided by a hosting company (hosting provider).
Namecheap offers web hosting services among the others they offer. You can either choose one from their offer or depending on your needs, you can choose some other out there like SiteGround, A2, Bluehost, etc. (just example ones)
But, there is a way to install/upload an SSL certificate directly to Cloudflare, but this option is available to Business or Enterprise users (customers).
Using your Namecheap SSL certificate, you can achive the
end-to-end connection using Cloudflare
Full SSL or
Full SSL (strict) option.