Go to your panel, then go to "Domains", then "Manage Domains". Then click on the DNS link under the domain mentioned in your post, and there you can "Add a custom DNS record to your domain".
As dreamhost clearly state: "This area is for advanced users only.
You are about to make custom changes to your DNS information.
If you're not sure what's going on here then you definitely do not want to make any changes.
Your DreamHost web hosting account will work fine even if you never ever visit this page!"
Be cautious while doing the change.
Hope this help,
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