Hello @majidelabd,
By default, we use the dompdf engine, which is not RTL-compatible. However, you can install the WooCommerce PDF Invoices & Packing Slips + mPDF extension that not only supports currencies, but all Arabic characters. This extension replaces it with mPDF, which adds support for right-to-left writing. So, in addition to seeing the currency, you’ll also be able to see addresses and other data in Arabic that your customers type in. Even better, don’t you think?
Here it is: WooCommerce PDF Invoices & Packing Slips + mPDF. To get this extension working, you just install and activate it as you would any other plugin. Finally, change the template to Simple RTL, under WooCommerce > PDF Invoices > General > Choose a template.
Let me know if it works! ??