Hello dear,

The syllabus, as well as concepts covered in both these courses, is quite the same but B. Tech CSE is a 4 year undergraduate course whereas MCA is a three-year post-graduate degree. That is the basic difference between them. MCA emphasizes on computer application development where as B. Tech is engineering based course with specialization in IT. MCA is generally assumed equivalent to  B.Tech  in CSE . If you ask my opinion you can opt for M.Tech after B.tech that could be a better option for career point of view.

Good Luck