Github pages on custom domain

Hi i have a static site with 5hmtl pages on my github repo i bought domain from go daddy and i used it to host my github repo i gave it to github pages. I have added CNAME in my repo which has my domain name and i have added ip as in github page documentation on the dns setting.
Thing done on the dns setting
All ip of github pages
185.199.108.153
…etc
And i
Added CNAME which point to my github

As <guruprasath-og.github.io>

Issues
1 My repo is not live on githubpage link which is default given by github.
When i search my domain
It goes to page called “lander”
2. I cant enforce https om github it say my domain is not eligilbe

If anyone if possible please guide whether im on the right track or not. Github hosting on custom domain is possible or not.

Im new hosting so please share some resource to learn this hosting process like assinging dns subdomains etc.