Do people with sleep apnea need 10+ hours of sleep? Eyes?

Yes, a person with undiagnosed/untreated sleep apnea might sleep for what seems like a long time because their sleep isn't restful. No matter how much sleep they get, it isn't enough because they aren't getting enough (or any) quality sleep.

I don't understand your second question. I have sleep apnea and I'm not aware that my eyes look any different than anyone else's nor has it ever been discussed in my 20+ years of CPAP treatment.

With the yes, I mean in people with undiagnosed sleep apnea. Their eyes will appear smaller, not as wide open as people without sleep apnea?

The answer to your second question is no.

Not only not diagnosed, but not effectively TREATED. Either condition will possibly have the person appearing to be inattentive, sleepy, with lidded eyes....yes. In fact, the problem can be narcolepsy. Note that there is a wide variance in how those with undiagnosed/untreated OSA or CSA appear and otherwise behave.

Do you mean, 'will someone with undiagnosed and untreated sleep apnea appear tired?' - yes, of course they will. I thought you were asking if their pupils looked different.

I was asking about the appearance of the eyes in general. Kind of like someone who is up way past their usual bedtime.

Also, is the "tiredness" of those with untreated sleep apnea like the tiredness someone without sleep apnea feels if they stay up late or don't get enough sleep? Or is it a different kind of feeling? Like you don't want to do physical activity?

Being tired, having 'brain fog', narcoleptic episodes (waiting at a red light, seated at the table, on a transit commute...), bleary eyes, bags under the eyes, cognitive deficits, inattentiveness, indecision, poor working memory, missing dates/anniversaries/birthdays/appointments/important meetings, irritability, strained relationships....these are all possible symptoms of sleep deprivation, poor quality sleep, and the other effects that arise from sleep apnea. Those other effects include heart arrhythmias, poor organ function, metabolic syndrome, weight gain, personality changes, dementia...

Mood changes, lack of motivation, loss of interest in hobbies and relationships, hostility and irritability (already mentioned) are possible due to poor sleep and being chronically oxygen deprived while sleeping.

If there is a situation where you must act does adrenaline override the urge to sleep?

It seems to me that you suspect that you may have sleep apnea. The best way to ascertain that is to get a sleep study done. Sleep apnea can be treated. Left untreated, it can be dangerous for you and others (see gloaming). If nothing else, a sleep study would ease your stress about the issue.

I do not live in the USA so I can't speak about costs of getting a referral, having a test or getting a machine.

Are you asking because you think you have sleep apnea or are these general questions about sleep apnea?