To translate your theme properly in your language there are few things you should do. Veterinary WordPress theme supports RTL and LTR both types of languages so you can use any language. But theme provides translation for only english and arabic. Thus you would have to translate theme into your own language yourself.
1) Go to wp-admin >> Setting >> General >> Select your language in option of Site Language. Once you do this theme will start displaying from RTL if your selected language would be RTL.
Now you are ready to translate theme into your own language for this purpose you can view this post how you can translate theme strings or words into your language. https://www.webfulcreations.com/translating-wordpress-theme-local-language-using-poedit/ Thank you.