Do orthodontics take molds on the same day you get your braces?

Usually no: Molds are diagnostic tools, usually generated at the same visit you have the rest of your diagnostic records (x-Rays, photos, exam, etc) generated. The Orthodontist will use these Data to plan your treatment. See an Orthodontic Specialist and ask them their usual office procedure.

Earlier: Dental models are taken during the record collecting part of the evaluation along with photographs, xrays, and other data. Models are taken also at the end of treatment, sometimes during treatment. Make sure you are evaluated and treated by a board certified orthodontist.

Molds of teeth: Each orthodontist does things differently. I personally take impressions of the teeth the day I place spacers. I place the braces the following week. In most instances, impressions for diagnostic study models are taken on a different day from when you get your braces on.

Most modern Orthodontist will do a 3D digital scan instead of impressions. These are often done the same day your braces are applied.