Hey,

Yes, you can do diploma in civil engineering. Here are a few colleges offering the course. Click on them to know more:

Government Polytechnic, Khamgaon - https://engineering.careers360.com/node/178060/course/108119
Government Polytechnic, Pune
https://engineering.careers360.com/node/178081/course/107828
Jamia Hamdard, New Delhi
https://engineering.careers360.com/node/4962/course/168144
Government Polytechnic, Nagpur
https://engineering.careers360.com/node/175889/course/102864
Government Polytechnic, Yavatmal
https://engineering.careers360.com/node/176402/course/105236
Banaras Institute of Polytechnic and Engineering, Varanasi
https://engineering.careers360.com/node/177944/course/109891
Government Polytechnic, Bicholim
https://engineering.careers360.com/node/177689/course/106250

All the best!