May I ask what error do you get when visiting your domain which is or isn’t using Cloudflare service, if so?
A great article about setting up an SSL for your domain at Cloudflare can be read in as a step-by-step instruction on the below article:
Below are some suggestions how to troubleshoot or check the settings regarding the SSL at Cloudflare:
Depending how did you get an SSL certificate?
Was it paid one?
Was it generated using a tool like Certbot or Let’s Encrypt (acme.sh, etc.)?
Was it created via cPanel AutoSSL?
There is an option to create an Cloudflare Origin CA certificate - max. up to 15 years. But, this SSL certificate is being trusted and for web traffic encryption only between Cloudflare and your origin/host server.
with it you can have Full SSL (Strict) mode enabled for your domain
Just to note, it also does not cover your e-mail service and you should not use it for your e-mail SSL.
Nevertheless, you should not visit your domain or a sub-domain(s) which are not being proxied via Cloudflare ( clouds) due to Web browser would show an error about SSL certificate not being trusted etc.
clouds) due to Web browser would show an error about SSL certificate not being trusted etc.