Why does the wifi on my computer work only some of the time?

[Windows Central Question]

I have an eMachine that is about five years old. Currently running 10. The wifi issues began to surface about three years ago and have gotten progressively worse until now the machine won't pick up the wifi for days on end. Then, suddenly, it will connect again for a few hours and then die off again. I have a gut feeling it's the card, but wanted some humble opinions. Thanks.