Step 1 : Log into your Godaddy account
Step 2 : Now go to My domains
Step 3: Click the settings icon and click Manage DNS
Step 4 : Now scroll your window there will be an option called "Nameservers" and now click change
Step 5 : Select custom option in the drop-down list
Step 6 : Now enter your Cloudflare nameservers
Step 7 : Now the cloudflare nameservers will be updated.