Can a double bed sleep two?

Yes, a double bed can sleep two people within the same double bed. But it would be quite cramped if you both move around a lot, I would not recommend using a double bed frame to fit two people that would not be too comfortable and you might struggle to get a good night’s sleep. You might want a lot of extra space for your bed so that it would not matter if you moved around in your sleep.

If you still want to use a double bed frame to sleep two people in the bed you might want to invest into a mattress topper so that it will reduce the amount of movement that you will feel by the other person that will also be in the bed so that the quality of sleep might be helped. But this mattress topper will only be needed if your mattress makes you feel the movement whilst you sleep if not, then you might have to purchase a new mattress topper.

If you are aiming for a bed frame that is smaller than a double bed frame to fit two people in the bed it would be uncomfortable for the two people in the bed if they are two fully grown adults. If you want to buy a bed for two people with the bed frame being smaller than a double, it will have to be for children or nothing else would normally fit more than one person.

If you are trying to fit large people into the bed, then maybe an XL king bed is an option for you since there will be plenty of extra space on the bed so that the two people will not collide while on the XL king bed frame.