You need to add quotation marks between "URL" -o "file_output" otherwise, curl doesn't recognize the URL or the text file name.
Format
curl "url" -o filename
curl "url" -o filename
Example
curl "https://en.wikipedia.org/wiki/Quotation_mark" -o output_file.txt
curl "https://en.wikipedia.org/wiki/Quotation_mark" -o output_file.txt
Example_2
curl "https://en.wikipedia.org/wiki/Quotation_mark" > output_file.txt
curl "https://en.wikipedia.org/wiki/Quotation_mark" > output_file.txt
Just make sure to add quotation marks.
