Is it permissible or impermissible to conduct transactions in "dropshipping" if the seller does not receive money directly from the buyer, but rather the money remains suspended on the website until the buyer receives the product, and the seller purchases the product with his own money then sends it to the buyer?

It is not permissible to sell what one does not own, except in a salam (forward) contract under specific conditions, such as the full payment of the capital at the time of the contract, which is not available in the described situation. Selling what you do not possess is prohibited by Islamic law.

There are two permissible ways to sell goods online that are not yet owned:

1. Murabaha for one who requests a purchase: You agree with the person desiring the item that you will purchase it and then sell it to them at a profit. This is merely a non-binding promise, and it is not permissible to request an advance payment. It is a condition that the item must be purchased and possessed before being sold to the customer. It is not permissible to request Amazon to ship the item directly to the customer; rather, it must be possessed first.

2. Agency for a fee: You act as an agent for customers and purchase items for them at the same price as the website in exchange for a commission, provided that the purchase is made with the customer's money, not your own. If you pay from your own money, it is considered a loan, and combining a loan with agency for a fee (exchange) is forbidden by Islamic law, as it falls under the category of "every loan that draws a benefit," which is prohibited usury.

Accordingly, the first method is permissible, subject to its conditions.