I don't know what this means.
Your Question is vague, you say you want to inject several lines, but fail to identify lines, or info you wish to inject. You fail to show incoming data that you wish to inject.
Or do you mean you wish to create a text file in that format.
Anyway with info you supplied all I could do is point you to a node I believe will do what you want. Again have a go and post back it you have issues.
A simple example to get you on your way.
[{"id":"4f75b206.fcb2fc","type":"inject","z":"30af2d3e.d94ea2","name":"","props":[{"p":"payload"},{"p":"topic","vt":"str"}],"repeat":"","crontab":"","once":false,"onceDelay":0.1,"topic":"","payload":"{\"one\": 1234, \"two\":\"some text\"}","payloadType":"json","x":220,"y":2240,"wires":[["753b44ea.15d59c"]]},{"id":"753b44ea.15d59c","type":"template","z":"30af2d3e.d94ea2","name":"","field":"payload","fieldType":"msg","format":"handlebars","syntax":"mustache","template":"here is a text file over several lines\nvalue one = {{payload.one}}\nYou can add text values to\nvalue two = {{payload.two}}","output":"str","x":420,"y":2240,"wires":[["27e88faa.4cbfb8"]]},{"id":"27e88faa.4cbfb8","type":"debug","z":"30af2d3e.d94ea2","name":"","active":true,"tosidebar":true,"console":false,"tostatus":false,"complete":"false","statusVal":"","statusType":"auto","x":640,"y":2240,"wires":[]}]