I have 10-month old mix breed puppy..i walk him 2mi everyday but still poops in the house at night..why?

During the walk he does all his business..and right before going to bed I will take him out and in the morning I have a surprise on the same rug. This does not happen everyday but it happens at least 2 a week. Also, I work from home and I'm there most of the time, but when I do have to leave him alone...when I return he has destroyed the house..the remote, picture frames..etc..he has plenty of his own toys but he has a field day tearing the home apart. I have to be completely honest..so I can get good advice..on occasions I have to give him people food such as grilled chicken strips or browned hamburger meat because my money runs low and that's what I have in the freezer for me and I don't want him to be hungry..until I'm able to purchase dog food(gravy train chunks in the can mixed with harris teeter dry food)..before learning better I use to put his nose in it and him...but after watching TV show "It's Me or the Dog"...I stopped and have been trying different voice tones...and sometimes rewards....this is only one of my questions...one of my others is he sheds ALOT...hair is everywhere....Could it be the food?...yesterday I did purchase a spray that is suppose to help...but have not used it yet...is there anything else I could do? Any and all help is appreciated...I actually have more questions but I'm going to stick with these right now!...I love him dearly and want to do whatever I can to better our relationship....But pooping and peeing in the house creates an awful smell in the carpet...yes I do put down puppy pads but he will go right beside it....I will move it to that spot and he will Still not do his business on the pad...Thanks again for any advice!