question

I thought they were required. But I found skills that didn't have them. I'm unclear on the requirements around these. I put them in because I figure it's a bit of extra protection. I found some templates on-line that I used. If you want to copy, look at, say, Knock Knock, follow the links. They should contain the reference to the original template I used.

Create an S3 bucket on AWS and expose it via https url. Then use those in your skill's configuration.

Yep, an S3 bucket is probably the easiest and quickest way to get a working privacy policy URL set up. That way, you really don't need to worry about the hosting yourself.