Hello. Thanks for contacting Careers360 and we hope we will be able to answer your query. 

Note that after finishing all your 4 semesters from your diploma, you can definitely continue to study in reputed institutes using lateral entry admission.

Joining a college after completing your diploma is called admission by lateral entry. You will directly get admission into 2nd year B.Tech there.

But, NITs don't have this admission by lateral entry system. Note that OJEE PG is an exam for pursuing your postgraduate studies in colleges in Odisha. 

For pursuing postgraduate studies in NIT Rourkela, you need to write the GATE exam.

Summary:

• After finishing your diploma, search for admission through lateral entry. 
• But, you can't join NIT Rourkela by this. 

Hope this helps you and all the best!