I move my domain to the Cloudflare server and there is no available on the web.
There is the statement " Great news! Cloudflare is now protecting your site Data about your site’s usage will be here once available" in the Overview section.
In addition, 24 hours have passed since the domain was registered on Cloudflare DNS.
I need to placed my Notion blog to my domain through the Cloudflare. Here is the instruction I used to to it:
But it still doesn’t work. Please help me.
Thx
I am afraid that’s a rather bad and misleading article you followed here as it suggests to make your site insecure by using a legacy mode which forces your site on HTTP.
Was your site working on HTTPS before you used Cloudflare? If not, then you need to discuss this first with your host and fix that.
The whole thing is quite messed up. For starters, mentioned advice does not only keep your entire site insecure, it’s even pointless here as this “approach” involves a Worker script which manually proxies to notion.so, and that site loads fine on HTTPS. You best let the author of that article know.
Secondly, with a Worker script, you either need to sign up for the paid plan or are limited to the allotment of free requests. Are you aware of that?
Unfortunately, custom development advice is beyond the scope of the forum and if there are issues with that script, you best reach out to the developer for assistance or post a question at StackOverflow.
My personal recommendation, try to find a host for your blog which supports custom domains and HTTPS out of the box. With workarounds such as this, you will only run into all sort of site issues.
They said me that I need to contact Cloudflare to receive a data required to instal SSL in my domain supplier.
I am not specialist so I have a little confused 
Cloudflare does provide certificates at Origin CA certificates · Cloudflare SSL/TLS docs but that is the same as any Let’s Encrypt certificate and will actually not work in this case.
As mentioned, you best move your blog to a proper host. Make sure your blog loads fine on your domain and on HTTPS, then it will also work on Cloudflare.