Customizing a Wordpress Site

Hello Freelancers, I purchased (Porto Theme) to build a semi e-commerce site (It will be in Arabic and English). The site will show products but instead of the client being able to directly buy the product from the website, he will be redirected to another subdomain to be able to complete the purchase. In short. 1. I want to make the product customizable so the user has to choose an option from a dropdown inside the product page to choose their option and then hit (Customize) instead of (Add to Cart), this button will lead to a subdomain link which is previously provided during the product publishing process. 2. The website is to be in both Arabic and English languages but I want it not to leave the page when switching languages. 3. For multi language, I don't want to use google translations, so please give a manual alternative to input the title, description..etc 4. The website is to be in USD/EUR/ILS Currencies. ILS is to be the default currency with the ability to add more currencies in the future. 5. I am in a tight deadline and need this to be done ASAP. 6. I have the theme bought for both Wordpress and Magento so please give me your opinion on which platform to go for based on science ;) Thanks Please share your thoughts and concerns