I had a PC I use for work crash recently and I got the less famous cousin of the Blue Screen of Death: the Black Screen of Death where Windows loads but not fully and you get nothing but a black screen and mouse cursor. Fortunately after three days of fighting with it it looks like I will be able to save the data on it and transfer it to another drive but had I not my last back up of the drive was four years old and I would have lost an unbelievable amount of important stuff. So don’t be me: back up your data.
If you’re not sure how, Windows 7 and 10 have creating an image built right in. It’s under Control Panel and Back ups. It takes a snapshot of everything you can overlay onto a new drive if need be.
Use some tool that creates backups without requiring action - the Control Panel thing is great but I’m assuming you can’t schedule it - and then copies it to that external drive without requiring action on your part. Because if you do that imaging manually, it WILL crash the day before you plan on doing it.
If appropriate, use cloud storage for the critical stuff. My employer actually has a deal with one such company, that we are allowed (not required) to use for business documents. For our personal stuff we use a different cloud service.