Trying to break dog of attention whining need advice

So we got a dog not too long ago, and right away we noticed it will whine and whine and whine whine to get treats whine for pets, whine if stop walking to pick up its poop on walks and won’t stop whining until I start walking again I saw advice on here to ignore it- turn away and not engage until the dog stops then reward for not whining basically. What do I do when it’s walk time? The second I put his leash on and our other other dog leashed up ready to go, the newer dog behinds whining yanking jumping non stop. I tried waiting him out to calm down for damn near an hour. He kept going incessantly. At that point I unclipped him and we just took the other dog not him because I didn’t want to reward the whining. Should I have taken him? What do I do in this scenario. It makes me feel so shitty but I’m so tired of the whining 24/7 he’s 5, we got him from an animal rescue league. He’s a great dog this is just his one thing and of course it’s the one thing I can not ignore or tune out. Please help thank you thank you thank you