Assuming it’s an Android phone, tap on Settings >> Network & internet >> Mobile Network >> Preferred Network type . You should see all the Mobile Network technologies supported such as 2G, 3G, 4G and 5G. If 5G is listed, then your phone supports it.
Read moreHow do I set my phone to 5G?
Switch between 2G/3G/4G/5G – Samsung Android
Read moreHow do I change my 5G settings on Android?
Switch 2G / 4G / 5G
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