I was thinking in doing many processus in an spreadsheet with app inventor for exemple, copie some rows ans paste in différents spread sheet. Make some updates and also introducing new Times pressing thé same bottom. And doing vlookup like in excel also when we send informations. Make additions and math opération pressing a bottom.
Is it possible to do all that ? Wich is the limite ?
However spreadsheets do not offer relations between tables and it looks like this is what you need?
You might want to look into working with relational databases. ...for example MySQL...
Just about anything is possible, if you put your mind to it. You can work with relational data on google sheets, but it takes some setting up...
With a good working knowledge of google sheets, google apps script and App Inventor you can achieve most things, but sometimes it does make sense to use the right tools for the right job (php/MySQL or php/SQLite or Redis for online, and SQLite for on device)