Hi Hirdesh,
For getting admissions into class 11th, you must know which stream you want to opt jn class 11th as it will decide your future. Also, it is better to make wise choice because it will help you to know what you want to become in future and what is it correct path.
See, every stream has their own career paths but no doubt science stream has many especially PCM stream.
Taking about your point of when to fill registration forms for class 11th. See, you can fill it any time after you finished your class 10th board. If you want to continue from the same school then donot worry you will be granted admission unless the stream you will choose manages with your board marks because some schools have restrictions about the marks and stream.
I hope this will help you. Thank you and good luck:)
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