Each way is a 2nd bet made at the same time and for the same amount of the win bet. It pays 1/4 or 1/5 (depending on the book) of the win odds for finishing in the top 4 or 5.
Place betting is wagering on a golfer to finish in the top 4 or 5 but without having a separate win bet. This way you're not forced to have a win bet if you don't want one. Olympic and 5 Dimes have place betting. Olympic calls it Show betting while 5 Dimes calls it Top 5.
I'm really surprised that Pinnacle doesn't offer either option.
FYI, Olympic pays 1/4 of the win price for finishing in the top 4, but 5 Dimes almost always pays less than 1/5 for finishing in the top 5.......sometimes a lot less.