Thank you for your detailed instructions.
I did it. But I get a "product not found" on the product card.
What I did wrong
1. I deleted all products
2. SEF URL
3. import product
products are available in the list of products. they have canonical URLs. But I get a "product not found" on the product card.
This is because do not created alias for imports of products
If I to save product in the backend - alias is created. and the product is available in product card. This is for a single product, but they are many...