what are the causes of cost push inflation and demand pull inflation?

Answer 1

cost push - related to the costs of supplying goods. Your costs are going up, so to supply the same amount of goods you sell at a higher price to cover your costs. (Or can't afford to sell anymore and supply is lowered so increases price.)

Demand pull - demand is increasing, so at the same supply people will pay have to pay more. This is inflation when the economy is doing well, so more people have money and want to spend it.