are there planets outside the universe?

Your approach of finding about a thing called "universe" is flawed in this respect. Nobody is going to define a universe for you to hang on to. Do it yourself. Figure it out.
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We're unable to know... At present, we *think* there may be other universes, but we aren't sure they exist. Other universes may not have the dimensions or forces that *allow* there to be planets - so, honestly - there's simply no way to know at this time.
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This is a nonsense question. We only know about THIS universe. We don't even know if there IS an "outside". If we know about something it must be part of the universe that we know. If there is anything else, we don't know about it.

Or does "universe" mean something different to you than to everyone else ?
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Most likely there are other universes, so yes.
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Is there a website outside of the internet?
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Should be, cant think this is the only system with planets