Kamalini's batting was all about precise placing and finding angles rather than power as England bowlers ran out of options against the left-hander.
Shafali, who has already played 51 T20Is, 21 ODIs and two Test matches for the senior team at the international level, looked in excellent touch as she toyed with the South African bowlers and put her side on course for a big win.
Invited to bat, Shafali, a regular in the India senior team, and Sehrawat, stitched a 111-run stand for the first wicket.
Australia put themselves squarely in the hunt for an ICC Under-19 women's T20 World Cup semi-final spot, after they outclassed India by seven wickets in their Super Six clash.
Opener Shweta Sherawat smashed an unbeaten fifty after Parshavi Chopra's triple strike as India notched up a comprehensive eight-wicket win over New Zealand to storm into the final.
A stunning spell of leg spin bowling by Parshavi Chopra led India to an emphatic seven-wicket triumph over Sri Lanka in their second Super Six match in the inaugural ICC Under-19 Women's T20 World Cup.
Gongadi Trisha was the player of the ICC women's Under-19 T20 World Cup, scoring 309 runs, including a hundred, while picking up seven wickets.
India stormed into the Super Six stage as they overpowered Scotland by 85 runs in their final group fixture of the ICC Under-19 Women's T20 World Cup in Benoni on Wednesday.
Earlier in the day, Nigeria ended their campaign with a thrilling six-run victory over Ireland.
Unbeaten so far in the tournament, a dominant India will start as overwhelming favourites to win their second consecutive women's Under-19 T20 World Cup crown when they take on also-undefeated South Africa in the final in Kuala Lumpur on Sunday.
India made an imposing 183 for 5 riding on Ghosh's exploits with the bat and then restricted Bangladesh to 131 for 8.
Rahul Dravid noted that the win was a landmark moment for women's cricket.
Regular knock out defeats at global events gives rise to serious questions
India are fretting over the fitness of their skipper Harmanpreet Kaur (shoulder) and Smriti Mandhana (finger) ahead of the opening game.
A night before the historic final against South Africa, the Indian women's team captain received a special phone call and it was none other than the history maker himself.
The BCCI is also mulling a couple of more windows in 2022 in case October-November is not feasible in India.
Shafali wants to make the visit to South Africa even more memorable with another silverware.
Batting icon Sachin Tendulkar believes India's squad could emerge as one of the standout sides in the inaugural the ICC Under-19 women's T20 World Cup.
'A Gold-standard meeting! Javelin thrower & Olympic Gold medallist @Neeraj_chopra1 interacted with #TeamIndia ahead of the #U19T20WorldCup Final!'
The Australia series exposed India's frailties in the bowling department and the team has a lot of work to do before the ICC event.
The WPL action is slated to be held on February 13 in Mumbai, a day after India's T20 World Cup opener against Pakistan.