And now what does it do when you connect it to the computer? Can it be seen in Windows Explorer, Disk management, Device management, or the BIOS? Does it make unusual noises when power is applied, or when you try to access it?
If it can't be seen, the usual first test is to remove the drive from the external housing and attach it directly to the motherboard, in case the problem is in the external housing.
On the other hand, a hard drive that is banged while in operation may be, I am sorry to tell you, broken and unrecoverable without spending a great deal of money. Or simply unrecoverable.
Going forward, have at least two copies of anything that you value. If you had backups, the solution would be as simple as restoring the backup to another drive. That doesn't do you much good right now, but may make your life better in the future.