Hello Dear,
if you passed 12th class then I would suggest you do Btech directly because you save your precious years and learn a lot.
but if you passed 10th, then you have the option to do diploma or 11th + 12th.if you do diploma after 10th then its benefit for you, you direct get a 2nd-year entry in Btech and you learn about the chosen stream.
good luck
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