I believe that a bachelor’s degree in civil engineering should qualify you to take the USPTO exam. Look on the USPTO website to be sure.
However, there isn’t much patent prosecution work in straight civil engineering, so he question would be whether you had enough knowledge in other engineering fields to be useful - for example in patent work in mechanical engineering.
For litigation, no specific technology is required but an engineering background will be helpful in being able to understand the technology involved in the litigation.
The important question is - do you want to give up working as an actual engineer in favor of only seeing engineering from the outside.