Futures and Options are derivatives traded based on contract between buyer and seller. In F&O contracts are based on expiry and strike price.
In futures, the buyer and seller both have rights to buy and sell. In option trading, only buyer has the rights to call or put at the contract end date and has no obligations. Option seller signs a contract with premium. In both F&O no real shares are traded. Strike rate and current market rate are base for the contract. Exchanges handle the transactions.