Ask a PA or AD if you're near an active/hot film set. They may also tell you the best entrance too.
You can't really choose the stage. But during the tour you will see some stages with your tour guide. We saw the soundstages of 'Dr. Phil' and 'The Doctors'.
We were allowed to enter one set but it was after shooting was done for the day. Guide told us that if set is hot, whether the light is flashing or not, set is closed.
We were allowed around 2 sets when they were not in use, plus the back lot sets
Nothing open!! Secret scene every time... Just one studio open... Dr Phill
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