You cant pursue BTech abroad, the Course is usually BS/B.Eng (4Years) abroad in most of the Universities abroad. As far as the Entrance is concerned for Universities abroad, SAT is widely accepted in most of the Universities abroad, however do confirm with you respective target university. Apart from this, you'll require English Proficiency Scores and a Strong All Round Profile, for Admissional Purposes abroad, especially if youre targeting some sort of Scholarship.

Since, you preparing JEE, I would advise you to prepare seriously now. Pursue BTech from some of the Top IIT/NIT/IIIT/GFTI. You may hence pursue your aspirations by pursuing MS/MEng/MBA/PhD Abroad depending on your interests, and perhaps more confidently after all the experience you gain during Graduation and Work/Internship Experience if any.

For more information about Studying Engineering Abroad do follow the link below

https://www.careers360.com/articles/study-engineering-abroad-what-you-must-know