My mouse keeps lagging/stuttering

So, I’ve been rocking this wireless mouse and keyboard setup from Logitech for about two years now, and honestly? It’s been smooth sailing until yesterday. Suddenly, everything started stuttering and lagging like crazy. I figured, "Fine, old gear is dying," so I went out and grabbed a brand new wired keyboard and mouse... but guess what? Same exact nightmare. Everything freezes up, the lag is real, and if I’m trying to type a post or a message, it just goes haywire. I literally tried typing a thousand words and ended up with "hello" repeated a thousand times.
Please, someone help me out here!
And if you could explain it like I'm five, that would be amazing because I am definitely not some tech wizard.
Thanks! 😵😵😵🙂🙂

First, you need to run a real thorough scan for viruses and all that other malicious garbage...

Second thing—maybe try turning off any nearby Wi-Fi gadgets or just moving them further away from your PC. It’s worth checking if you're dealing with some RF interference messing things up.