Cloudflare
How to deploy astro js project in to cloudflare
For first make sure you have push your astro js project in to github repo. Read here , how to push on github →
Next you need to create account on cloudflare
Create Cloudflare Account

Access on cloudflare official website - and create new account.
Worker and Pages

Now you can click on workers and pages menu area.
Create Application

Next you can click on create application button. - then select pages - and click connect git
Github Repo

Select your github repo project , click next , on framework you can select astro, and click save and deploy.
Finish
And congratulations , now your website is live !!

Next you can add custom domain, click on custom domain button, and add your domain.