Instead of making pandan extract with the leaves and coconut water, can one just use prepared pandan extract? And if so, how many drops would you reco

I alway always use the real leaves, the flavour is fresh and unbeatable. If you can't get it, the bottled stuff is quite strong, have a taste as you go and use a few drops. To me, it doesn't take as lovely as fresh leaves

I've never used either pandan leaves or pandan extract, but I was able to find this on the subject:

How much pandan extract should I use?
It's a lot stronger than essence and should be used sparingly; ¼ -½ teaspoon of paste is enough to flavour a cake; note that it also leaves a lurid green tint. By comparison, when using essence, you need 2-3 teaspoonfuls to flavour a cake or batch of pancakes, depending on the strength of the particular brand. https://www.sbs.com.au/food/article/2016/02/23/10-ways-pandan

The message here (and on a few other sites that I found when looking into this) is that substitutes can be very strong, so I'd be judicious, erring on the side of too little rather than too much. I hope this helps. ;o)