Vipul,
your son has a solid horoscope overall (especially for profession) and he is currently under Mahadasha of very strong Jupiter placed in lagna since 9/9/2010 (with excellent combination in nakshatra and sublord)
Seems like he is seeing someone already and chances of marriage are best during Jup-Sun period from 22/3/2021 to 8/1/2022. Slight chances of marriage also exist during Jup-Ven-Mer period (8/9/2020 to 24/1/2021).
God Bless,
Astrologer Deepak