I press on the first red dot but the semi circle not show up as the lesson on this video
https://drive.google.com/file/d/1DTgc2dt4q_KbVSuyHj8hDJSl14unhFEa/view?usp=sharing
3 point circle
The projected semi-circle appears to be irrelevant to the task. The third point clicked on the small circle appears to be coincident with the larger semi-circle, so Fusion 360 is projecting the semi-circle. I'm not sure why the author is using a three point circle to create the circles on the top sketch. A simple projection would work better (assuming the circles are actually circles and not ovals).
Also the project appears to be poorly organized with bodies in the top node instead of components. See Rule #1.
ETFrench
I think the difference you see is because Auto Project edges on reference default setting is now off, in the past it was on.
If you want it enabled look in preferences. Most experienced users turn it of and only project what they need. Also pretty sure whoever made the video could have pressed P and projected the circles, but as @etfrench mentioned maybe they were not true circles
Mark
Mark Hughes
Owner, Hughes Tooling
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I see you asked the same question here and got the answer about auto project.
Mark
Mark Hughes
Owner, Hughes Tooling
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Should mention the red semicircle that gets projected is a mistake and is a good example of why you'll probably want to turn auto projection off with a bit more experience.
You can see a bit earlier in the video the edge from one of the parts below the sketch is highlighted when the mouse pointer passes over it. The person making the video accidently picks that edge rather than the third point on the small circle. If this is your teacher they need a few lessons themself!
Mark Hughes
Owner, Hughes Tooling
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