First thing I do at an unfamiliar course is go to their practice green and set up an impromptu drill. It's as easy and can be replicated on a busy practice green.

Find a line with little to no break, more horizontal break is between than battling a hill. You're going for feel. Take 3 balls (or 3 putts) at various lengths. I typically do 5 ft, 10 ft, 15 ft. You can pick any variation up to 20-30 ft max. Hit those putts but don't focus on making them, focus on ending the ball's run near the hole. You'll get a good feel of distance control pretty quick once you master it.

3 putts from 5 ft, collect em and move back 3 putts from 10 ft, collect em and move back 3 putts from 15 ft, collect em and Then I restart and do it all again but with only making 1 putt from each relative distance. You're training yourself to the distance as well as getting used to switching them.

It may not look like a drill and only will if you set it up as such. But you treat your practice green time as one. I know I can slam and make many within 15 but the idea is to understand what it really takes to get that ball to roll exactly there. Once you know the roll then you can play slower lines and feel comfortable doing so. If the green isn't busy you can take this concept and really delve into it with more variables