Decimals on prestashop

I have prestashop 1.7.6.4, I need a module to allow using decimals on some products for quantity Changes that must be apply: 1) on the BackOffice: add a property for products, so i can activate/deactivate decimals for quantity 2) must indicate how many decimals should be activated Observation: - consider some product got "product with combinations", on that case one of the combinations should be allowed with decimals. for example Kg. See picture: product with [login to view URL] - if the product doesn't have combination, plese check picture product without [login to view URL] 3) for product with activated decimals for quantity, allow user to select quantity with decimals on the front office. check pictures: front office with [login to view URL] frontoffice - unit [login to view URL] 4) also if from the back office i need to modify an order and add a product with activated decimals, i can select the quantity with decimals. see picture: [login to view URL]