The 22-year-old featured in just four of England's qualifying matches, while Aston Villa's Morgan Rogers appeared in all eight, underlining the selection dilemma facing Tuchel in the number 10 role.
Asked if Bellingham had a fight to make the starting lineup, Tuchel was unequivocal.
"Yes, he has," Tuchel told reporters. "He knows he is one of the starters, but we have 14 or 15 potential starters.
"These roles can always change, but at the moment I think there are 14 or 15 proper starters and Jude is one of them," he added.
England are preparing for their World Cup campaign in Florida, where they opened their warm-up schedule with a 1-0 victory over New Zealand in Tampa on Saturday. Harry Kane scored the only goal.
Bellingham captained the side for the first time during the second half of that game, with Tuchel rotating his lineup in the hot and humid conditions.
Despite the competition for places, Tuchel said he had been encouraged by Bellingham's recent form following injury.
"He looks good in training," the German said. "I think he is at the moment in a sweet spot because he has had his break and has the hunger to be back on the pitch."
Tuchel has emphasised squad depth and flexibility ahead of the tournament, indicating that several players are capable of starting while others may be used to impact matches from the bench.
Tuchel would not confirm whether Bellingham is part of his leadership group, but said on Sunday that midfielder Declan Rice will serve as England's vice-captain during the World Cup.
England face Costa Rica in a friendly on Wednesday before kicking off their World Cup campaign against Croatia on June 17 in Dallas.