Back when I used the Steam Deck as my main PC handheld, I forgot the sudo password I'd created the first time around. Naturally, I started to panic and thought I'd need to reflash my Deck and lose all my data, but then I found a solution that let me reset my Steam Deck's sudo password in just a few minutes. All you need for this is a wired keyboard (or a wireless keyboard with a dongle and a USB dock) and some focus, because there's some typing involved.