What is the ruling on subscribing to an AI investment website that funds advertisements and operates on a cashback basis, with a referral system for inviting friends, offering a loan voucher worth $50, and requiring funding the "robot" with one's own money to withdraw profits? Is this considered a loan that brings benefit, or does it involve other dubious elements?

Investment in this manner is forbidden due to Sharia-related concerns, including the inability to control the displayed advertisements, guaranteeing a percentage of profit to the investor, and the transaction combining a loan (salaf) with a compensatory contract (mu'awadah), which is prohibited in Sharia as stated in the Prophet's saying: "It is not permissible to combine a loan and a sale." Furthermore, jurists have agreed that every loan that brings a benefit is usury (riba), which is forbidden.