Write the value you want to pass to the flow. You can also use variables to send a list of values if the flow uses a delimiter ( , ). For that you need to inject in the Jenkins Job additional environment variable. You can use EnvInject Plugin !

E.g:
    192.168.0.1
    8080
    

E.g: Using variables:
    Inject properties in the build:
    list_of_ips=192.168.0.1,192.168.1.0,192.168.2.0    
    ${list_of_ips}
    Inject properties in the build:
    list_of_ports=8080,8090,9000,9100
    ${list_of_ports}