Hello abhi, Age doesn't matter for for some limit for eg if your age is between 15-24 you can apply for b tech after surely after that it will be a matter of consideration though you there are many insititute which will give you admission if youare a keen learner.
As per your age i.e. 25 there will be no problem provided you have knowledge required for your field.
Candidates can check B.Tech Cut off for Top IITs & NITs here.
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