We do not offer web hosting services at iwantmyname, so we can't provide a website login, FTP, SQL, or similar services for uploading website software, code, etc.
You will need to set up a web hosting account, and there you will be able to upload your website content. In your iwantmyname dashboard, you would update the domain's nameservers to those of the new hosting provider, or add their DNS records in the domain's dashboard.
To update nameservers, login to your account and click on the domain you want to update. Click update nameservers, and on the next page, delete all of our nameservers showing. Replace them with the nameservers provided by your web host. It's fine if there are only two or three nameservers and not four. Save the settings, and you're all set.
After that, any DNS additions or changes will be done in your hosting account control panel, not in your iwantmyname dashboard, as our DNS management is deactivated when external hosting nameservers are in place.
Note that you would also need to have external hosting in place to use DNSSEC or for an SSL certificate.
You can see our recommended web hosting partners here, or you are welcome to use any hosting service you prefer.