So basically you are looking for a rank of less than 2000 or say 1500 to be safe in TS Eamcet.
If you are in a IIT coaching centre then make yourself clear on what you want. You can assess yourself at the end of first year. Are you able to make it to top 5 of your class in weekly tests or not. If you are finding it hard to make it, forget about IITs and NITs, I dont want to demotivate you but you have to pick 1 path finally you cant put your feet in 2 boats. And CS from CBIT and VCE are no less colorful than core branches from NIT’s , you can check placements and packages from their websites, they are great.
Eamcet gives good weightage to Inter marks if I remember. So you must go all out for your Inter exams.
Try scoring 960+ to be safe and No compromises here, give your best performance in all the exams and practicals, dont underestimate those marks and its not that hard compared to upcoming competitive exams.