A debt is a great concern, it affects our affairs in our day to day life. You need to firstly ask Allah to assist you in repaying your debt. And ask him to assist you to get married. Then you need to write out a plan as to how you intend of repaying the debt. And then work with the plan you have designed. As for avoiding sins, it is difficult, but try your best to abstain. And if you fail repent and start again. Allah’s door never closes.