Hello,
Your question is a little unclear. Please mention yojur question in detail. If your question is what carreer oppurtunities you have with a polytechnic diploma in civil engineering, then-
You can go for btech lateral entry
You can apply for PSUs etc.,
You can go through the link below, to know what all carrer oppurtunities you have-
https://m.jagranjosh.com/careers/after-polytechnic-courses-1528887111-1
Good Luck!