The beta test is only available for note 20 series in India. You might have to wait a bit to get one ui 3.0, I think that samsung will role out one ui 3.0 in the first quarter for 2021 for the m series
very soon u want to test it. that's new well my dear u have to wait for at least 6 months. as samsung always takes out in 4 to 6 months time interval its update.