The 17-year-old was the subject of speculation after national team manager George Burley refused to rule him out of a shock senior call-up.
Instead, Fleck is in line to make his Scotland Under-21 debut during the UEFA Championship qualifying double-header against Albania.
The midfielder met up with Billy Stark's squad for the first time on Monday and has been tipped to start in Albania on Saturday.
Fleck said: "It's great for me as a young boy to be picked at this level.
"We have two big games coming up against Albania and I have to thank George Burley for giving me this chance.
"There was a lot of talk about me possibly playing against Holland this weekend but to be honest I never listen to things like that.
"I am still only 17 and have just broken into the first team at Rangers.
Right now I am just very pleased to be picked for the 21s for the first time and if I can make my debut, even better."
However, Fleck, who has made 11 first-team appearances, is not counting on making his debut at this level just yet.
"When you look at the squad, there are a lot of lads playing first-team football every week so I won't be going there expecting to start," he told Rangers News.
"I will try to impress the coach like everybody else and if I play I will do my best to help the team.
"Over the years I have played for Scotland at different levels and when you pull on the jersey it makes you very proud.
"If I get that chance again in the next week or so it will be a big thing for me so I will give 100% and hopefully we can get a couple of victories."