Puppy constantly getting pet on walks

I recently adopted an 11 week old lab puppy. Adorable, yes. A lot of work, yes. I live in a big city, next to the city’s main large park. It’s nice to be able to easily take my dog to a huge green space. But it’s making me seriously lose my mind how many people stop to pet my puppy. I don’t mind if we’re just standing around, but when I’m clearly trying to train a puppy or get her under control, it feels insanely rude to ask me to pet my her and start asking me questions (even worse when people don’t even ask…). I work from home, so take her out frequently between meetings. I’m already in a rush trying to get her to use the bathroom and not be distracted by squirrels, other dogs, etc., and on top of that I have at people stopping me at least 5x on each walk. It literally makes a 15 min walk a 30 min walk. Aside from it being extremely rude to my time and my puppy’s training, I worry it will stress her out always being touched, or cause her to get too excited every time she sees someone as she grows up. Has anyone else dealt with this? I don’t want to seem rude by telling people no or asking them to stop, but I also care a lot about my dog’s well-being and my personal time!