Hello. Thank you for asking your question on just answer. My name isXXXXX will try to help.
Has he had anything to eat, at all, in five days?
Is he drinking water?
Have you tried canned cat food or tuna?
Is he still active and playful?
He's had two bites of roast beef and 1 piece of pop corn.
He's drinking water.
Have not tried canned food or tuna because Iprefer to use dry.
He's still active and playful.
Even though his main diet will be dry, I would try some canned food, or a little tuna in water, just to get him eating.
He may prefer canned food.
If he does like the canned food or tuna, you can start to mix that in with the dry food.
If he will not eat the canned food or tuna, then he does need to see a vet. 5 days is a long time to go without eating. Usually I recommend no more than 2 days without eating.