Sorry, you can't do it without a physical remote. Depending on the device (as long as it's not a stick), you may be able to get away with a cheap universal remote. If the device was previously connected to Wi-Fi, you can configure your current Wi-Fi to match what the device last connected to (same SSID/network name and password). If it has never been connected to Wi-Fi or was factory reset then you must have a physical remote unless the device supports a wired connection.
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