The US stock market is open Monday to Friday from:
2:30 pm to 9 pm Nigerian time
1:30 pm to 8 pm Ghanaian time
You can place a buy or sell order for a stock when the stock market is closed.
If you buy or sell a stock when the market is closed, the order can only be executed when the market opens.
The order will also be executed at the market opening price which may be different from the price you ordered at.
You will get an email notification once the order is executed and this email will include details of the execution price.