An algorithm is a step-by-step guide to doing something with code.
What I’m suggesting is that you Google how to calculate factorials recursively. And then use the algorithm (the written steps) as a guide for setting up your blocks in Thunkable.
If you instead want to use your method, you would need to store the current product in a variable so that you can multiply it by the current value in the loop (5, then 4, then 3, etc.).