No, if you are talking specifically for IIT, then you cannot get admission in IITs on the basis of JEE Mains score only.
For that, you will need to clear the JEE Advanced exam.
But, you do not have to worry as there are also good
colleges accepting JEE Mains scores, you can get admission in various top private colleges as well as IIIITs by using your JEE Mains scorecard.
Some of them are:
Thapar University
BITS Mesra
LNMIIT Jaipur
IIIT Hyderabad
IIIT Bhubaneshwar and
many other.
You can get the list of all colleges that accept the JEE Mains scores, from the link that I have shared above.
Hope this will help..!!
Best of luck.!!