If you want to uninstall WordPress from Namecheap then you can do it with different steps that are explained in the article
A subdomain is an additional domain that can be used to provide more features to your customer so read the article to add subdomain Namecheap
Namecheap is cheap and No. 1 Domain Registrar around the world. So follow this guide for transfer to Namecheap from Hostinger quickly
After buying web hosting from Namecheap now it is time to install WordPress on your Namecheap to build and manage your website.
Are you a beginner, want to get a website? by following this guide, you will get the namecheap web hosting for your WordPress website