questions on matrix and date

Hello I would like to know:
-With which formulas I can retrieve the data of the matrix on a cell precise example result of the colone 2 row 2

can I perform a calculation on a specific cell example column 2 and row 2

-Then I treat them with a csv spreadsheet

finally the date module allows me to display only a fixed date of delivery for the customer to 3 days 5 days and 7 days depending on the order date and is it possible to add a maximum hour for the passage of the command. example 18h cloture orders and delivery dates pass on the day after for delivery date
exemple: https://www.pixartprinting.fr/petit-format/impression-cartes-de-visite/

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