how do immigration of some country check your travel history for migration verification? [closed]

Some countries require e.g. criminal records from all the places you have resided in the last X years. That would be the most important thing to satisfy the “good character” requirement. There will also typically be an interview, where contradictions could create problems for you. A few countries might also share data on things like immigration violations but that's not very common and I would be surprised if the UAE and Australia did. In that context, criminal convictions are the most relevant, it's not obvious that some unpaid private debt would necessarily stop you from getting a visa.

But if your question is whether you can successfully get a visa, residence permit or even citizenship in one country when you have some past immigration violations, debt or even criminal conviction at the other end of the world, the answer is yes. Even if some of this might in fact disqualify you for some visas in some countries and there are procedures to vet applications, there is no global system that would ensure each and every country has direct access to all the relevant information.

On the other hand, if your plan is to lie about your being in the UAE at all, you need to realize this is quite risky. If you are found out (and many things can betray you: Are you planning to create a fictional employment history? What about the web?), your credibility will be durably damaged, not by the outstanding loan itself but by your attempt at obtaining a visa fraudulently.