There are multiple drive tests.
SMART attempts to predict failure.
A drive may display 100% with excellent by SMART and still fail a drive test.
Drives can be used until the terminal event as long as files are backed up to another drive or the cloud.
Also make backup images to have a quick method to restore an image to a new drive.
Before the drive fails you may have performance problems such as slow read, slow write, hangs, freezes, unexpected shutdowns and restarts, etc.
With the lower cost of replacement drives you can replace the drive now rather than dealing with any later anxiety that may occur.
To test the drive:
Run HD Tune (free version) (all drives)
HD Tune website
Post images into the thread for results on these tabs:
a) Health
b) Benchmark
c) Full error scan
Run Sea Tools for Windows
long generic test
Post an image of the test result into the thread
SeaTools for Windows | Seagate
How to use SeaTools for Windows | Seagate Support US
Post images for all steps and results:
https://support.microsoft.com/en-gb/help/13776/windows-10-use-snipping-tool-to-capture-screenshots
For any problems posting images please use share links: one drive, drop box, or google drive
These steps can be performed overnight:
a) HD Tune full error scan
b) Sea Tools for Windows long generic test