can I use free domain n hosting?
You can but it’s a terrible idea - slow loading, downtime, bad user experience etc.
Basic paid for shared hosting is not expensive (few $ a month) and will make a noticeable difference even from someone like BlueHost, HostGator, GoDaddy
Unlimited free host will run well at the first time, but after some weeks, it will slow, freeze…
But you could use it for testing
I’d add that while unfortunatey files often end up on warez sites these free hosts are like gifting it to them.