Andy M.
Certified Pretend Chef
I think you had about the right amount of charcoal. But perhaps you lit too many or all of them initially. I usually dump a chimney worth of charcoal into the kettle with only about the bottom third of the chimney lit. Many folks like to first bank a pile of unlit charcoal in the kettle and then place a few fully lit charcoals onto it and then slowly watch the kettle rise to desired smoking temp. You want to catch and stop the temperature as it is rising.
The undesirable white charcoal smoke will eventually disappear and if you threw in wood chunks you should see blue smoke venting out.
I typically get at least 3 hours of smoking temp with a single chimney worth of charcoal with plenty of fuel left for searing.
Do you mean I should fill or almost fill a chimney and light it then pour it into the grill before it's completely burning?