RE: Maven and Jenkins
I cannot give you full setup , but will surely help you with some pointers
why you require maven? , i assume just for dependency management , if yes then there is very nice tutorial on toolsqa which you should follow .
Once you have maven setup with Testng then running it on jenkins is pretty straight forwards, install maven plugin (may be it is pre-installed) –> create new Job with template as Maven –>Configure the job and add you root pom and your goal to build(mvn clean install)
And i think you are done , simply run the job