Of course, you have to provide an unmarried certificate, stating that you’re absolutely single and ready to solemnize a marriage. This is actually a legal document called a single status affidavit that clearly states the matrimonial status of the person. In foreign, it’s challenging to verbally convince foreign authorities, especially the foreign ministry that you’re single. With the legalized introduction of a single status certificate, you can easily prove it. This is how your purpose would be fulfilled, which is to get married abroad.
There may be some other purposes like employment and study in the overseas country. These conditions may arise the requirement for the attested proof of your single status.