Have a look at the CSV module as well.
https://appstore.home.mendix.com/link/app/108605/
This lets you take a FileDocument that you may have uploaded, and iterate over it line by line in a Microflow. It creates an entity per row with an attribute for each value. You design the entity to have the right number of attributes and name them numerically. The module will fill them in numerical order.
When I use it I have it create a non persistent entity for each line that I then use to create a persistent entity, validating, converting, and creating associations on the way. I then delete the non persistent entity to free resources and move on to the next line.
It’s a well documented module and there is an example in the module to help you on your way.
What do you need to do during the loop?
There’s an excelImporter tool on the app store where you could upload your csv, break it down into some staging tables, then loop through those, that’d be my first suggestion