Germany face Hungary in Duesseldorf on Saturday, having said goodbye to 2014 World Cup winners Manuel Neuer, Thomas Muller and Toni Kroos, while captain Ilkay Gundogan has also retired since the home Euros in the summer.
Joshua Kimmich was named Germany captain on Monday and Fullkrug, who at 31 is now one of the more experienced members of the squad despite making his debut in 2022, said his side would be hungrier.
"We've lost players with an incredible amount of experience and success. As Jo (Kimmich) said yesterday, we've got no more world champions in the team.
"Of course it's a disadvantage, but we want to turn it into an advantage. We want to be a troupe which may be inexperienced but we're hungry, greedy for success."
Fullkrug said a team that had not won anything "wants success just a bit more than a group that has had it".
Fullkrug singled out Mueller's absence, saying Germany was already missing one of the country's best-known characters, both on and off the pitch.
"When he walks into the room he has a real presence. Since he left, of course, it's been a bit quieter," Fullkrug said smiling. "But we still miss him."
The centre-forward has 13 goals from 21 games for Germany, coming off the bench in all but six of those matches.
Fullkrug moved from Borussia Dortmund to Premier League side West Ham United in the summer, having spent his entire career in Germany.
He is yet to score or assist in four games in England, three of which he came from the bench.
"I still need a bit more time to settle in," Fullkrug said, adding that the Premier League was "more physical and dynamic, but less tactical" than the Bundesliga.
