in future in india one plus 7 support 5g or not?
No....and neither will the 7 Pro.
Afaik there is need of special hardware for the 5g functionality. That's why they launched a separate 5g version of the pro. Also, really don't see true 5g coming to India in atleast the next two years.
You can buy OnePlus 7 5G (not launched in India yet) to get a 5G service
Yes it'll support 5G.
Performance Tips for the OnePlus 7 Pro
by KnightofScorpio, 2019-07-16