Creating training data in Rasa

I am new to rasa. I have a csv file containing 49453 example data. I have so far been entering data manually in localhost. Is there a way to do upload the csv file. I tried converting it to markup and json format but the files generated are not in the same format that rasa wants. Is there a way to convert this file and upload. How do people with a lot of training data upload their data into rasa as intent and entity?

I, neither, do not understand how to enter the training data to the server, according to the doc (HTTP API)

Do you have any idea? The old tutorials had examples that we could replicate at least.