Thank you, dear @osmanburcu. Thank you for your time.
I tried to follow the steps but still felt that the way to upload my data should be simpler. I kept searching the internet for a few days and came up with the solution.
In fact, it was @Kal_Lam who, in another consultation, had given a successful and simple solution. I leave the link here for future readers.
The solution is to use ODK ingrated with a Google spreadsheet. In this way, the data stored is completely editable for the end user and is updated as soon as the data is loaded from ODK Collect (the mobile app).
With this steps, anyone can upload old data (excel, csv, etc) to a simple Google spreadsheet. And, this spreadsheet will grow with new data from the ODK Collect users.
I know that this solution is not for KoboToolBox, but I had read that Kobo will soon allow integration with Google spreedsheet as the ODK project.
