Hi @Anonymous,
I see that you are visiting as a new member to the AutoCAD forum. Welcome to the Autodesk Community!
In addition to the great and quick suggestions by @j.palmeL29YX and @ВeekeeCZ, please make sure that you start a new drawing using an ISO (not imperial) template. If you have already started with an Imperial one, you can use "-dwgunits" to pick MM as the units for your drawing.
If you need to see this in a video, please let me know and I am happy to make one for you.
Please select the Accept as Solution button if my post solves your issue or answers your question.
John Vellek
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