First off you should own lots of disks so that redundant copies of important data does not get lost. This guide is not an easy solution and a disk may be wiped when repaired. The clicking sound is generally caused by a faulty logic board.
Replacing the logic board requires the exact make and model disk to swap parts from. This will generally requires the disk to be formatted as the spare sector tables etc are all reset etc.
The screws on hard disks are usually #7 or #6 Torx so you need the right screwdrivers. There are not many and they are not hard to remove;
Reassembly needs to be careful to align the replacement board with the ribbon to the drive motor and the heads.
Once the screws are replaced try powering up the disk. If the clicking is gone then the logic board was faulty if not the disk assembly is toast.
To recovery files, expect to pay big bucks. This is due the need to copy the ROM from the old disk over to the new one. This means lots of soldering.
This does not always work, if the heads are damaged or worse the media is scratched.
Reading this post should remind you to have a redundant backup. NASA reported a 75% failure with an archive so beware that storage is far from perfect.
Laptop size disks stuffed into a USB box are low cost and modern disks have TB capacities. We recommend using 3 or more for higher redundancy and safety against the unthinkable.