Hey there @Gabriel_Mingorance, welcome to the forum!
You're almost there!
From what you say you are happy with users being able to modify values from different rows. If that's the case then you should change the Action Type on your query to Bulk Update via primary key, and select the column on your database that is the primary key.
Make sure that in your table settings you have selected a primary key (right above th3 columns settings).
Some of my clients don't like to have to click on a save button and prefer more of an "excel feel". So what I do is trigger the query from a table "Change Cell" event and remove the save button. As such for every change the query runs. There is a split second until the database returns refreshed, but they're fine with that.