I presume the plot was sold in the financial year 2012-13 relevant to the assessment year 2013-14 but you did not either file the return or did not disclose the LTCG in the return.
If the amount received by you on sale of the plot is more than Rs 10 L or even the amount deposited in your Savings Bank account is more than Rs 10 L, you should have normally received a notice from the IT Dept. Pl. check the compliance part in your account in the efiling portal.
If it is reflected, you need to respond to the compliance requirement suitably, preferably with professional help. If it is not reflected, the chances of the IT Dept issuing a notice are remote, though not ruled out.
You will not be able to file IT Return now. You also lost the opportunity to declare the income under ICDS. However, you can explore the possibility of disclosure under the new Disclosure Scheme.