Here it is right from Briggs(first 5 hours):
https://www.briggsandstratton.com/na/en_us/support/maintenance-how-to/browse/how-to-change-oil.html
Thanks. That is very informative on at least five points. But first Briggs & Stratton says use 30 weight oil. Then at the bottom they have a chart with 5 oil choices. 4 of which apply to where I live. I am inclined to go synthetic with frequent oil changes say every 40-50- hours. I like sythetic because a fraction of the synthetic will get up high and start lubricating the engine immediately. Quicker than straight 30 weight.