That is a preprogrammed remote, you're stuck with whatever's preset by the built-in code. Its not a learning remote where you could teach any missing commands.
There are some Universal remotes like the Inteset 422-3 or the One-For-All urc-7880 that allow you use advanced codes, these are 5 digit codes for individual commands like the option key. For the Onn Roku tv, the preset code in the above remotes is 14398, the option key is 00254.
Edmund Roku Community Streaming Expert
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