Stop using that device. And do a full review of your security procedures and habits.
Never use a Windows computer using an account with Admin privileges.
Never use the same password on more than one account.
Never use the default admin credentials on a router.
Ensure you're using good WiFi security with a secure password.
That's just a start. Failing to do these things leave you susceptible to being compromised.
Now, if you're suggesting that a Roku device was the point of entry into your network, you really need to ask advice from someone who knows about this stuff. There are so many ways to compromise systems without trying to hack a limited action Linux-based streamer.
DBDukes Roku Community Streaming Expert Note: I am not a Roku employee.
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