Oil loss at Twingo 1.2 – Really motor replacement necessary?!

Hello dear Twingo experts & lovers, I have been the happy owner of a used Renault Twingo 1.2 Liberty, built in 03/1999, type C06, 128 000 km, 43 kW (58 hp) (I bought the car from a used car dealer without warranty.) Unfortunately, my Twingo has been losing oil for about a week. Since no oil pool was visible, but the oil lamp was constantly flashing and the oil level sank rapidly again and again, no matter how much oil I poured, I went to the workshop. The only way to save the car would be to install the engine + repair the broken parts or a new engine. Cost point at least 800 €. Since this is unfortunately already more than half of the purchase price, but I would like to keep my car absolutely, I wanted to ask if you could have any experience with this product. blem have and know what the problem with the mysterious oil loss is? If the engine really should be replaced, do you have an idea where I can get a used but working engine for my Twingo? And maybe also if there is a cheaper installation and expansion option than the above mentioned? I would really be very happy about a feedback because I’m pretty desperate right now and I really want to save my beloved Twingo! Momenta I can still drive it, but I have to measure the oil level every 2 days and drop oil, which unfortunately is not a permanent solution with the oil prices 🙁 Thank you already in advance for your help!!! Best regards from Cologne, Nike Z.