Uploading a pdf file into a Swagger API page in C#

I am working on uploading a pdf file and performing redaction on it. Issue is I am using a web application where I want users to be able to upload a pdf file and they can then execute the redaction method. Is there a way for the users to directly upload a file from their file explore

I am looking for something similar to the code snippet below but if there are better solutions, I am open to that as well.

public FileContentResult(  fileName, string redactReult = "redactedFile.pdf"){

     ...

}

So I am looking for something similar to the above code snippet or if there's another method for the users to upload their file, I am open to that as well. 

Any help is welcome. 

Thank you.