Hi.

If you the spelling error is minimal such that it does not change the word or the surname completely then it will not create any problem. However, when the authorities verify the name on your admit card and from your identity card such as Aadhar, if they ask only then mention about the error. Usually they understand you made a spelling error. However it should not be excessive such as the surname is Singh and you wrote Verma or any other surname. Singh and if you write Simgh by mistake, will be ignored.

Good Luck