Assuming you would like tips on how to make your Bixby voice assistant talk when you plug it in:
To get started, open the Bixby app and select the three dots in the top right corner. From there, choose Settings > Voice wake-up. Once that's enabled, all you have to do is say Hi, Bixby whenever your phone is plugged in to make it start talking.
If you want to be a little more specific, you can also enable the Trusted voice option in the same menu. This will allow you to wake up Bixby even when your screen is turned off, as long as your phone is plugged in. Of course, this means that anyone could theoretically wake up your Bixby if they know the phrase—so use this feature with caution.