Question

Is anything in the universe is at rest

Answer 1

Yes. Nothing in the Universe is ultimately at rest. If all reference frames are valid — and I'm told that they are — then in your own private frame of reference, it is (sort of) valid to say that you are at a standstill, relative to everything else. Likewise, Earth can be considered "at a standstill," with the rest of the Universe engaged in a bewildering dance around us ...

But since every atom making up your self (and everything else) is in constant motion, nothing is not really "truly motionless" after all.