Hello.
There is quite big difference between data science and data analyst ,
One data analyst work on numbers and he goes through the entire insight, identify trends and make his strategy and present his variation in the form of presentation through charts and graph, here data analyst do only one thing dominantly which is analysis of data for any organisation or in any other specific area.

While data scientist require knowledge in various fields , data scientist can also work as a data analyst, here  in one view data scientist consists various skills includes, advanced programming, machine learning, data analyst,very good mathematical knowledge etc.
While in data analyst some business skills are Sufficient these includes mathematics , statistics, business, with an analytical focus etc.
Here one data scientist work with algorithms ,his main task is to design algorithm and implement it according to the insights received from a  data analyst , his main purpose is to make a complete module with a analysis of insight .


Now if it comes to BTech in data analyst so in a broad spectrum it is BTech in data science and data analyst, as BTech is a four year UG program where there is complete focus on the theory as well as practical part so here entire syllabus of four year will make you able to have good knowledge of coding, machine learning....., Good knowledge of data analysis also so after this course you will be having a good knowledge of data science and in a right way you will be called data scientist as you can also collect insight data by yourself too.
Now if it is about BCA in data science so here it is 3 year UG program and in these complete three year you will be having theoritical as well as practical knowledge on data science part dominantly and quite knowledge of data analysis will also be there but in comparison of BTech course content and level will be less .
If it is about BSc in Data science then I think you better know that Bsc is a 3 year UG course here main focus will be on the theoritical part.
So overall BTech in data analyst can be a better option and BCA comes on second, and rest depends upon your desire and  vision that where you are mainly focusing, theoritical knowledge or practical knowledge or both .
Best of luck.