Q: When I select vertices on my object they turn yellow and red, what’s wrong ?

If your vertices turn yellow and red while selecting them then you have “soft select” turned on.

5

Sometimes you want more than just one vertex to move as you want to manipulate or “deform” an area.
You can select the B key on your keyboard to activate this feature. If you want to turn it off, just hit the B key again ( it is a shortcut key )

By holding down the B key while left clicking ( hold and drag ) you can increase or decrease the affected area.

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