there are multiple options to do this.
1) DB translation
Store -> Configuration -> Advanced -> Developer -> Translate Inline -> Enabled for Storefront set to Yes
2) You can do via theme transaction if you have made a custom theme as per your language.
i.e en_AU, en_US
After this do the following
php bin/magento deploy:mode:show
php bin/magento deploy:mode:set developer
Clear cache and static and deploy
sudo rm -R pub/static/*
sudo rm -rf var/cache/ var/generation/ var/page_cache/ var/view_preprocessed/
sudo php bin/magento setup:static-content:deploy -f
Let me know if you have still any query than add me in skype : samumaretiya.
Thanks,
Sam