Can Kleeneze put me in prison if I don't pay them back the money?

I was doing Kleeneze catalogue job for one year and I was working hard walking many KM to far places just to get customer orders.Even my legs was hurt because I was desperate for money and walked everywhere to get orders hoping that I would get good bonus,money from Kleeneze but I ended up without money and with big debt.I owe 300 euro to them with interest and charge.My Kleneeze sponsonsor told me that I will earn 350 in a week with Klenneze but it was all lie.From all the customer orders I got I only could keep myself 20 euro and not more.I couldnt even buy catalogues for 20 euro.I earn 20 euro,I have to pay for catalogues 28.00 euro and when I got orders I deliver them to peoples houses with car which is worthless because I also have to pay for petrol as well.Klenneze is a scam and I am not going to pay them that money 300.I worked so hard just for 20 euro which I have to give away anyway. I told them that I can’t afford to pay them back 300 and they told me to pay back monthly 18 euro or they will call on my house outside Debt Collector.They keep writing me threatening emails to scare me.They are not even polite. They keep asking my address,phone number.But they also have my photo. Do You guys think that they would put my photo in news to find me or would they be capable of calling police if I run away to another country and don’t pay them?They are scam they dont deserve that money which I worked so hard for. What do You think guys should I pay them back monthly or should I just stop worry and not pay them,keep that money to myself and go to live another city?I am confused,please help.What should I do?Can they find me and put in prison me for not paying them that money?