If a put is bearish, why is a seller of a put bullish? I’m really conf...

Every transaction in the market consists of 2 parties: a buyer and a seller. No one would be able to buy a stock, bond or option if another party was not willing to sell it to them. The purchaser of the put is absolutely bearish and is betting that the stock price is going to fall. The put buyer pays the premium to acquire the right to sell the stock at the strike price. The premium is paid to the seller of the put contract. In exchange for the premium, the seller takes on an obligation to purchase the stock. Because the seller is now obligated to purchase the stock, the seller is considered to be bullish on the price of that stock. If the seller was bearish and thought the stock price was likely to decline they would not want to buy the stock and would not sell a put. Commit this to memory, the right to sell is bearish and an obligation to buy is bullish.