My other question is, ok my dad is paralized from the right side down, will lymphoma attack the left side also, he is able to speak and think ok.?

Possibly. Depends where the lesion is. If the brain likely just that side. If the spine then may progress to effect both sides. Radiation can be used to stabilize or improve his condition. Lymphoma is also very sensitive to chemotherapy.
Possible. Lymphoma can affect peripheral nerves and brain tissue too.