What are the different folders of my domain for?
The different folders we can see in web hosting from FTP access help us organize the files of our websites.
By default, domains registered in DonDominio (It may vary with each provider) point to the /public/ folder of the web space. For the files to be visible from your domain (http://www.tudominio.com), they must be uploaded to that folder.
If you want to create a new website on a subdomain, such as "http://tienda.tudominio.com", it is advisable to use a completely different directory than one that already has a website. For example, the /tienda/ directory at the same level as /public/.