Hi there, Ibrahim!
Alexa here with the Shopify team.
At this time the checkout language in Shopify POS is compiled code on the iPad so we cannot use the same system to translate the checkout.
Currently, the only part of Shopify POS that is available for translation are the printed receipts. They are available in German, French, Spanish and Portuguese. They will automatically print in these languages if your iPad language setting is set to them.
To view what the is capable of change for POS receipts, visit this help doc.
Hope this helped answer your question!
Alex | Customer Success Guru | Shopify
Our Sufio automated invoicing app will cater to your needs. Apart from many useful features, your main concern to send invoices and receipts in multiple langauges (including Arabic) will be taken care of.
Our support department at email@example.com will also be happy to assist you with anything else that you'll need.
Hope this helps!