A sell-to-open order establishes the Short Position call side of a covered call. After owning at least 100 shares, you sell a call contract to open the position and collect premium. A buy-write order bundles this sell-to-open call with the purchase of the shares so the covered call is entered in a single trade.
The premium provides income and a partial hedge against modest declines. If the call expires worthless, you keep the shares and the premium. If price rises above the strike, you may face Option Assignment and deliver the shares.
Each time you sell to open a call, you create or roll a covered call position. The process can be repeated weekly or at any cadence that fits your strategy.