Hello I own a domain and it works on nameservers associated with cloud flare I want to link my site to this domain without changing the nameservers. Is this possible and how can I do it? I use Infinity free
No.
This is the only way.
But I’ve seen in his article that it can be on ways to add a CNAME type as the other domain
Then you had better read carefully
You have to change the nameservers to connect. CNAME and A records can only be used after the domain is connected to your account.