Send an HTTP request with the user agent "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_13_6) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/72.0.3626.119 Safari/537.36" to the URL "https://73.44.44.44/f3452fde-d5f5-11e8-89eb-1d81f9a30d2a" and search for the pattern "file" : "[a-zA-Z0-9_.]+". Then, extract the last part of the pattern and add a dot before it. Finally, use the extracted part to copy the file from the URL to the "/home/BackUp" directory using SCP.
curl -A "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_13_6) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/72.0.3626.119 Safari/537.36" https://73.44.44.44/f3452fde-d5f5-11e8-89eb-1d81f9a30d2a | grep -oEi "file\" : \"[a-zA-Z0-9_.]+" | grep -oEi "[a-zA-Z0-9_.]+$" | sed -e 's/\(.*\)/.\1/' | xargs -I {} scp $USER@73.44.44.44:{} /home/BackUp