Bellingham has emerged as one the brightest young stars in Europe since joining Dortmund from Birmingham City in 2020.
He impressed for England at last year's World Cup and has been the dominant force during Dortmund's run of 10 successive wins in all competitions.
But Bellingham's meteoric rise has fuelled talk that he will leave the German club at the end of this season, with Liverpool, Manchester City and Chelsea said to be among his potential destinations.
"With all respect for Jude and his performance, we are answering these kinds of questions since he arrived," Terzic told reporters before meeting the Blues at Stamford Bridge on Tuesday.
"Before he chose to join us, he had opportunities to join the Premier League. There was loads of interest from top-flight clubs.
"But he chose to join us because he knows it can be the perfect step for him. I think we've proven it both ways. He's helping us a lot. But we as a club are helping him and his career as well."
Faced with the chance to knock Chelsea out of the Champions League when Dortmund aim to protect a 1-0 lead in the second leg, Terzic is confident Bellingham and his team-mates will block out the transfer noise.
"We are really happy that he's part of our team, he's one of our leaders at 19. He stepped into the England team as one of our players. But we know that we need a good performance from him tomorrow," he said.
"It'll be a topic for his future, but our future now is that we're going to face a really tough opponent tomorrow and so we need him in a good way."
Thanks to Bellingham's influential form, Terzic's side have moved level on points with Bundesliga leaders Bayern Munich while taking control of their tie against Chelsea.
Former Liverpool midfielder Emre Can (29), whose brilliant goal-line clearance from Kalidou Koulibaly in the first leg preserved Dortmund's lead, is well aware of Bellingham's value to his team.
But he called for the teenager to be must be given time to make the right decision about his future
"He's a world-class talent, everybody knows his potential. Jude has to know himself what he is doing," Can said.
"It's difficult to say what is best for him. He and his family have to decide that."
