Is there anyone that can help my dad get a mattress?

Check with the Goodwill, Salvation Army, or any of the numerous places where people make donations of household good... I know these places won't take used mattresses but sometimes there might be a mattress that is brand new that was donated.

He is on Medicare but does not need a medical bed ...He just needs a full or queen set....and of course can not afford one...and just one of us cannot afford it...was looking for some kind of help...thank you so much

If he is on Medicare, the cost of an adjustable bed and good mattress will be covered 80% if there is a prescription from his doctor for it.