I think you will give the NOIS improvement exam when you pursuing the BTech.

Hello,

No you cannot give improvement exam after taking admission in B.Tech college. You can join the B.Tech college after you have completed your 10+2 level. Until and unless you have completed your 10+2 level you cannot get admission in any B.Tech college. If you get your improvement exam score before taking admission then you can use your improvements score for the admission in B.Tech college.