Do I have to own the stock to sell call options

No, you do not have to own the stock to sell call options. A call option gives the seller the right, but not the obligation, to sell the underlying stock at a specified price within a specific time period. This means that you can sell a call option even if you do not own the stock, as long as you are willing to sell it if the option is exercised. However, if you sell a call option without owning the stock, you will be obligated to buy the stock at the strike price if the option is exercised, which can be risky if the stock price rises significantly above the strike price.