Computers don’t last forever. In general, people replace computers(desktops, laptops, tablets) after no more than 5-6 years, or start having problems and start complaining.
They can. Before I left the UK I had a System 3 Cromenco with 12 inch floppy disks, CPM operating sytem, IIRC 64k of RAM and a steel case that would literally have stopped a bullet. Still worked fine, if you like that sort of thing.
Exactly. A computer can be expected to last 10 years or thereabouts. It can last much longer, but at some point finding suitable replacement parts may become difficult and it will be more practical to get something newer.
8 1/2 years is a very long laptop life.
It’s about the length of a good PC. A cheaper one … probably 3~4 years before you notice how slow it’s getting.
Make sure it’s clean and dust-free inside
Get a new SDD and extra RAM
And/Or your OS probably needs to be reinstalled
But move your data off the installed drive first!!! It’s probably not worth too much effort at this point to fix it, unless you are willing to try Linux or ChromeOS or another ‘light’ OS.