My husband's EF is between 10-15. He does very little right now. He can take care of himself as far as showering, getting dressed, and making a meal, if that meal is breakfast cereal or heating up a plate at lunch. He goes up and down stairs. That's about it.
Thankfully he is able to work from home, and he does 2-3 hours worth of e-mails each day. Thus far he's had an extremely understanding employer.
He has a few good hours each day when I suspect he probably could do a little more, but he's fairly tired from lack of sleep, too. I do want to ask about light exercise (like going for a walk) at next doctor's appointment.
When your heart's ejection fraction falls below 35% it is considered as being "low". 15% is very low.
As your heart needs to pump blood to all tissues and organs just to sustain them, the 15% will be needed for that. Additional tasks will be hardly possible.
Ejection fraction can however improve over time, so dependent on the cause of the low EF (i.e. heart attack), improvement might be seen in the coming time.