I've only one attempt to give JEE i.e. in 2019, and I don't want to drop, should I prepare with B.Tech or with B.Sc to be secure?

Once u enter into BTech or Bsc,it is impossible to design a time table which allows u to concentrate on both academics of JEE and ongoing college activitiesnIf u R really determined to crack the xam,u can take a risk of dropping an year else continue BTech and work hard in scheduling a proper strate