Deploying projects on subdirectories of custom subdomain

How do I host/deploy projects on subdirectory of my custom subdomain I want the projects to be served on “projects(.)myname(.)com/project1”, “projects(.)myname(.)com/project2”, and so on. All are react or Next.js projects that are hosted on netlify and I want to continue using netlify servers. I don’t want the user to be redirected to netlify subdomain like I want everything to be on the subdirectories of my custom subdomain. User should never see netlify URL. I have read of the monorepo approach but that won’t work for me.

P.S. - Using paranthesis because without them url shows at “mysite availabe for sale” or something along those lines.