DNSSEC question and Cloudflare

[UrgingOfc]

Hello,

I have a question relating to DNSSEC and Cloudflare.
I'm using the free DNS https://desec.io/ but they say that I need to set up the DNSSEC. How can I do it on my domain?

Also, I wanted to use Cloudflare DNS, but when I try to add it, it says that I need to use a domain name and not a subdomain. Is there a way to use Cloudflare that I don't know?

If I can't use Cloudflare DNS, how can I implement some of the protections of it to my subdomain?

Thanks in advance.