Robinhood does not support market orders for options contracts due to greater volatility in the options market relative to equities markets. Placing limit orders will give your order a better chance of being executed at the price you want. This way, you’ll know how much you’re going to pay to buy a contract. For the same reason, we also don’t support stop orders.
You can place Good-til-Canceled or Good-for-Day orders. Your app’s default setting is Good-for-Day, but if you’d like to enter a Good-til-Canceled order, you can simply tap the clock icon and select Never Expires when you place your order.