Steam workshop (BP/C++)

How can I upload to steam workshop from ue4 using a button and specifying a text file (that’s a map file, all level objects are stored in *.txt). And then later after subscribing to that workshop item automatically download it in game directory (I already know how to get the game directory) or it can hold all the text data of level and then in game I can easily save that string/text to an external txt file. Any help please, very hard for me as a beginner at ue4. Thanks.