Hello Aspirant,
You have not mentioned any stream here so i am giving you example of b.tech government colleges.
If u r a science student Appear for the JEEMains, secure good marks. U can get into state govt. B. Tech colleges even if u secure 50-70 marks(for GEN category) (Can varry according to different States). Rank is decided according to your final marks (40% of 12th exam and 60% of entrance marks). And then u can apply to any govt college you want and if u deserve, u will get a seat.
If u want to get into IITs, if have to secure good marks (being in 20% students among your state board students and your AIR should be <150k)to be eligible to appear JEEAdv.
All the best for your future.
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