I tried this kind of program. Its working but too lengthy and not flexible. I want to add few more things in it, which may make it more complecated. Any good idea to make it easy and comfortable to modify (to add few more topics)
Will everything be present already or do you want more to be added by an admin user? I have already made a similar app but using CloudDB.
I'll be adding for 6 subject about 90-100 url. Further if I add more streams, it become complicated and difficult to modify
Hmmm, perhaps you could name the tags in this format - "Class-Subject-Chapter"
e.g - Class 6-Maths-Integers and then when you use list pickers you could simply store the selections in respective variables and use the join text block to join the variable values.
I want to do the same, Can you tell how?
Yes I am making the code for that itself, just give me some time.
Pl send me only that part
Test_Trials.aia (6.4 KB)
Tried and Tested. Please tell if this works or not @abhijeet_h. 
Also, you can add more to the list by adding more items to the variable list itself just follow the same pattern.
Thanks Mayank, I'll check the details and let you know. But are you really 10 yrs old?
Yes I am still in Grade 6 and we were introduced to app inventor this year in July, I was on scratch before this.
Its Great Mayank, Its working nicely.
Good to know