Australia will be firm favourites to knock off the runs in the fourth match of a tournament characterised by one-sided contests so far.
Afghanistan have included all three spinners for this tie – Rashid Khan, Mujeeb Ur Rahman and Mohammab Nabi.
A target of 161 was never likely to test England, with Roy proving as much in a 46-ball innings that included 11 fours and four sixes.
Mohammad Nabi scalped three wickets while Dawlat Zadran and Rashid Khan scalped two wickets each for Afghanistan.
Gulbadin Naib's Afghanistan face Australia in Bristol on June 1 in their World Cup opener.
The Afghanistan pair of Rashid Khan and Mohammad Nabi are at second and third respectively.
Mark Adair was their chief tormentor with figures of 4/19, while Boyd Rankin took 3/40.
Simmons, who took up the position in December 2017, said that the time is right for him to move on after accomplishing his goal – to help Afghanistan reach the World Cup.
Delhi Capitals now face Chennai Super Kings in the second Qualifier in their bid to make it to the maiden IPL final against Mumbai Indians.
Keemo Paul, who had earlier scalped three wickets, hit the winning runs as Delhi Capitals beat Sunrisers Hyderabad by two wickets.