Dean Henderson, Conor Coady, Ainsley Maitland-Niles, Kalvin Phillips and Jack Grealish are also hoping to win their first caps over the next few days.
After facing Iceland behind closed doors in Reykjavik on Saturday, England are away to Denmark in the Nations League on Tuesday.
“Everything we’ve seen on the training pitch, I’d have no hesitation in starting any of the players that have been with us,” added Southgate.
“That’s why they’re picked in the first place, but you’re never certain how they’ll adapt and fit in with the group.”
Grealish is a doubt for England’s first game since winning 4-0 away to Kosovo in a Euro 2020 qualifier on 17 November 2019.
The Aston Villa captain has been nursing a knock although Southgate said it was “not too serious”.
England will be out for revenge when they travel to Reykjavik to take on Iceland in Saturday’s Nations League clash.
The Three Lions have unhappy memories of playing against this opponent, having suffered a shock Euro 2016 last 16 elimination at their hands.
However, having won their last three matches by a combined 17-0 scoreline, the Three Lions are clear 1/4 (1.25) favourites with bet365 to put that behind them with a win here.
What time does Iceland vs England kick off?
This Uefa Nations League match will take place on Saturday, September 5.
The Group A2 clash will kick off at 5pm UK time – that’s 4pm in Iceland.
It will be played at Laugardalsvollur in Reykjavik.
The other two teams in Group A2 – Belgium and Denmark – will play on Saturday evening.
Goalkeepers: Hannes Thor Halldorsson, Ogmundur Kristinsson, Runar Alex Runarsson, Patrik Gunnarsson
Defenders: Kari Arnason, Ari Freyr Skulason, Sverrir Ingi Ingason, Hordur Bjorgvin Magnusson, Jon Gudni Fjoluson, Holmar Orn Eyjolfsson, Hjortur Hermannsson, Alfons Sampsted
Midfielders: Birkir Bjarnason, Emil Hallfredsson, Arnor Ingvi Traustason, Victor Palsson, Arnor Sirgurdsson, Samuel Fridjonson, Mikael Anderson, Jon Dagur Thorsteinsson, Andri Baldursson
Forwards: Kolbeinn Sigthorsson, Jon Dadi Bodvarsson, Albert Gudmundsson, Holmbert Fridjonsson
Goalkeepers: Jordan Pickford, Nick Pope, Dean Henderson
Defenders: Kyle Walker Eric Dier, Kieran Trippier, Michael Keane, Trent Alexander-Arnold, Joe Gomez, Tyrone Mings, Conor Coady
Midfielders: Declan Rice, Mason Mount, James Ward-Prowse, Phil Foden, Jack Grealish, Ainsley Maitland-Niles, Kalvin Phillips
Forwards: Raheem Sterling, Harry Kane, Jadon Sancho, Tammy Abraham, Danny Ings, Mason Greenwood