I can't snap my fingers. At all.

Spelling is not my fortaa, fortae, fourta…. I ain’t good at it.

I can't remember anything

Adulting

Swimming properly. Sure, I can stay afloat and move effortlessly in the direction I want, but it's nowhere near the swimming strokes they tried to teach me in PE when I was a kid. I never managed those.

I only have a vague idea of how to make coffee.

I feel like I am the antithesis of this question.

When I was a kid, I had a difficult time learning how to whistle, and so I decided I would learn all of the "stupid human tricks" that I could, and now as an adult, I don't know of any common skill that I do not have at least an advanced beginner or intermediate level.

Maybe you can help me by identifying what you believe is a common skill and then I'll see if I know it or not and respond.

I keep typing the wrong words. Not just typos but entirely different words than what I intend to type.

Starting new things that I don’t already have a very clear understanding of the process for

Driving.

I can't whistle with pursed lips.

This means I can whistle pretty well like some kind of ventriloquist, but if I try to do it "properly" I'm either way off key or I just make a sad windy noise.

I have these stretchy old people shoestrings so I never have to tie my shoes again.

It's not that I can't tie my shoes. I can't keep them tied.

Making decisions and whistling

I'm really horrible at cooking, so I prepare myself the simplest of meals. Examples include: putting sugar in the microwave in order to make caramel and creating a little fire hazard, microwaving noodle soup with a raw egg in it hoping it would both boil the water and cook the egg (it just exploded and it took some minutes to clean up properly), making what I thought was pancake batter mostly with eggs and then eating something that resembled omelettes covered in maple syrup more than pancakes, burning most of the rice and undercooking/overcooking most of the meat I eat (and up until recently I would just put the heat on max because "why would you waste time?"), etc etc. Thankfully, my palate is underdeveloped so I can live with my "cooking", but my wife evidently hates it and tries to keep me as far away from the kitchen as possible unless I'm there to clean, lol.

Math, can't do math to save my life

I can't whistle, or immediately tell right from left. Give directions with East, West, North and South.

I can't sit cross legged

Can't swim, can't whistle and the weirdest of all: can't hold my breath.

Not being able to swim is mostly related to that last one, as when I tried using a mask I was doing reasonably well.

Singing the right note.

I do enjoy singing but enough people have told me I'm tone deaf to know not to do it when anyone's around.

But when I'm alone in the car, or everyone else is out of the house, I put the radio on loud and enjoy "tunelessly warbling" (as my older daughter puts it) to my heart's content.

(They're also not at all keen on Kylie Minogue, but I don't think that's a skill issue.)