How to have diffrent app on same domain for e.g. mysite.com and app.mysite.com

Hello everyone, I have a question regarding deployment. so i have vite+react SPA app which is bad at SEO i think. So I am thinking to have 2 apps ( static app website typical html,css,js ) and my main app. so I am thinking if mysite.com(server static seo friendly web app) and app.mysite.com(serves my actual app that is currently deployed).

is it possible to do this ? how will deployment work, will it still work if i have 2 different code repos ? Help me out. thanks

Yes.

The easy way would be to set up two different sites in Netlify.

You can refer to the Custom Domain documentation here:
https://docs.netlify.com/domains/get-started-with-domains/