Substack or Author Website? Or Both?

I’ve noticed many authors now use Substack, even though I don’t currently have one. I’ve also noticed a lot of those who use Substack don’t seem to have an author website.

For those familiar with Substack, would you recommend having both? Or is an author website sufficient?

Also, if I do decide to use Substack, is it best to embed it into my author website?

Would love to hear your thoughts, tips, or personal experiences! Thanks in advance.