My dad is a 96-year-old vet and my mom is 86 -years-old and needs assisted living. What finanical aid is my dad entitled to?

go to the nearest VA medical center and ask to speak with the service officer if possible take your dad with you they can tell you what he is able to receive from the VA, veteran affairs.
You maybe able to get information from the VA web site,
http://www.vba.va.gov/VBA/
Hope this helps!