hi,

bachelor of technology is engineering oriented course. there is various streams like electrical, mechanical,  civil, electronics and communication, which considers as core engineering stream. where computer science engineering, information technology and IT oriented stream. bca stands for bachelors in computer application. bca  course and some similarity with IT, Thus bca graduates are also eligible for programmer, web development roles such as b.tech IT student.

however in some of the companies or organization, bca graduates with Mca (MASTER OF COMPUTER APPLICATION) are only allowed for software developer or programmer role. so if you are inclined towards computer science related field you may take btech or bca course. through for career growth b.tech in cse or IT is more favorable.

now coming to free course, there is no college available where is zero tuition fees. however government colleges has less of fees then private ones, also based on academic score or financial isues, financial aid or scholarships are available for meritorious students.

follow the below link to know about government bca colleges in India:

https://it.careers360.com/colleges/list-of-government-bca-mca-colleges-in-india