Second-rower Wells and centre Kelly join club colleagues Freddie Steward and Joe Heyes – who made their debuts in the win over the USA last Sunday – and vice-captain Ellis Genge in the starting line-up.
Kelly starts alongside 39-cap Henry Slade in midfield, and Wells is paired with Bath’s Charlie Ewels at lock.
Eddie Jones includes two other debutants, with wing Adam Radwan and No8 Alex Dombrandt given their opportunity in a team captained by Lewis Ludlow.
Jones said: “Our focus this camp is being as strong a 36-player squad as we can be and there has been a lot of hard work and intense competition.
“There is a responsibility on the 23 players selected to perform to their personal best.
“We want to go out there and put smiles on the faces of all the supporters.”
England versus Canada is live on Channel 4, with coverage starting from 2.30pm.
15 Freddie Steward (Leicester Tigers, 1 cap)
14 Joe Cokanasiga (Bath Rugby, 10 caps)
13 Henry Slade (Exeter Chiefs, 39 caps)
12 Dan Kelly (Leicester Tigers, uncapped)
11 Adam Radwan (Newcastle Falcons, uncapped)
10 Marcus Smith (Harlequins, 1 cap)
9 Harry Randall (Bristol Bears, 1 cap)
1 Ellis Genge (Leicester Tigers, 29 caps)
2 Jamie Blamire (Newcastle Falcons, 1 cap)
3 Joe Heyes (Leicester Tigers, 1 cap)
4 Harry Wells (Leicester Tigers, uncapped)
5 Charlie Ewels (Bath Rugby, 22 caps)
6 Lewis Ludlow (C) (Gloucester Rugby, 1 cap)
7 Sam Underhill (Bath Rugby, 23 caps)
8 Alex Dombrandt (Harlequins, uncapped)
16 Curtis Langdon (Sale Sharks, 1 cap)
17 Beno Obano (Bath Rugby, 2 caps)
18 Paul Hill (Northampton Saints, 5 caps)
19 Callum Chick (Newcastle Falcons, 1 cap)
20 Lewis Ludlam (Northampton Saints, 9 caps)
21 Dan Robson (Wasps, 13 caps)
22 George Furbank (Northampton Saints, 3 caps)
23 Joe Marchant (Harlequins, 5 caps)