How to transfer files from Linux to android using the command line. (Linux/Fedora26)?
On your phone:


Open Settings > About Phone
Click on Build Number 7 times
Go to Settings > Developer Options
Enable Developer Options and enable Debug mode on USB


On your computer:


Install ADB on your computer. You may refer to this guide, although it isn't for Fedora, the steps should be similar.
Use adb push/pull to copy to/from your phone. To transfer a file to your phone, use adb push filename.extnsion /sdcard/0/ and substitute the path to the sdcard accordingly for your device.