can I seed and use weed and feed at the same time?

It is not recommended to use a "weed and feed" product during time of seeding. The concern is that the chemical that controls weeds may have a residual effect that will damage the seedlings. It is best to wait until the seedlings have been mowed one or twice before applying any chemical. A simple starter fertilizer should be used at time of seeding instead of a "weed and feed".