How to create a part at assembly? If I have a sketch (2-D) at assembly what to do next to finish this sketch and part?
You actually need to start the process with Insert/Component/New part. You will be prompted to select a plane or face as the basis of the part, and then a new part will be started with the sketch open, and an InPlace mate to hold it in position in the assy.
Go to the Help and look up Creating a Part in an Assembly.
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