3g/4g And Wifi Connection At The Same Time

[guiduz]

Hi all,
I am an owner of a Mi5s Plus, I'd like to use 3g/4g and wifi connection at the same time.
Is this possible?
I tried to turn on the option keep active both data and wifi connection, but it seems not work.
I need it because i must connect to a decvice wifi (without internet connection), but to uprgrade it i need internet connecion. I do not know if I explained.
Thanks

 

[vladpaul]

Deleted

 

[vladpaul]

You can set phone to switch between wifi and data when wlan conectivity is poor.