Look for a mirroring app on your phone's control panel. Enable it and it should look for available devices to which it can mirror your phone screen.
Each manufacturer may have its own name for this feature. On my Lenovo tablet it is "Screen Cast". On my Samsung tablet it's "Smart View".
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Streaming Stick 4K+ 3821 | Streaming Stick+ 3810 | TCL Roku TV 43S245/C107X