Hi ! Yes you can upload your text files to the Hub. Then in order to define the configurations and how the examples must be read from the text files, you must also upload a dataset script in the same repository as your data.
If you don’t upload a dataset script, then the default dataset builder for .txt file is used (and basically it concatenates all the text data together).
If I understand correctly your dataset is a parallel dataset like flores, so I think to make your dataset script you can get some inspiration from the flores dataset script 7. Also feel free to read the documentation you mentioned about how to create a dataset script.