One of the important techniques for international SEO is using hreflang, which is an attribute that lets search engines know the language and geographic target a page is meant for. It is very useful if you have a site catered to an international audience, meaning that it targets visitors from several countries or languages. Hreflang in HTML attributes defining how the website pages in different languages ​​or regional targets are related. In this way, users in different locations are shown the version of a page that is the most useful to them, contributing to a better user experience and lower bounce rates.
First the pages you have in different versions by language or location should be identified. After those hreflang tags are added into the section. For example, you have a page made for users from Singapore in English and another for users from Japan in Japanese, for users in different countries hreflang tags are added to each version in order to specify the relationship. Also, you need to add hreflang tags to your site so that people from other countries can see which page is already set to the main language.
For example, tag tells search engines that this version should be viewed as the primary page for international users from different regions or languages. The absence of those tags or errors in coding can result in your pages not being indexed and ranked correctly. Hreflang used in the right way results in improved international SEO, plus Google or another search engine will be able to specify and show the version of the page most suitable for users from other countries or languages.