My suggestion. If you have to start small, then start small.
Maybe first quit drinking sodas, then give up fruit juices, dried fruit.
Then after a while add in others to give up like potatoes, legumes, grains, rice, etc
Finally give up all processed foods. If it comes in a box, don't eat it.
PS Most store trail mixes are loaded with non-paleo items like crackers, pretzels, dried fruit, peanuts, and cashews.
Shopping list is tough, everybody likes different things, beets are good for you but I won't eat them, yuck!!!

I try to keeps steaks, bacon, eggs, fish, chicken, and shrimp in the house for meals.
For veggies I like spinach, asparagas, brocolli, carrots, cucumbers, mushrooms, and spring salad.
Check the labels on any salad dressing, most have High Frutose Corn syrup(you don't want that)
For fruit I eat a lot of pears, blueberries, strawberries, kiwi, oranges, plums, cherrys, mango, bananas, and apples.
For nuts I like pecans, walnuts, almonds, pine nuts, sunflower seeds, macadamians, and brazil nuts.
Cavemen didn't go to the gym either so that's no problem. I have a cheapo treadmill I use if it's too hot to walk outside. I prefer just walking outside thou, get some sun, see the sights. Some light free weights are good to have for toning. Maybe a jump rope, chin up bars are good to have and cheap to make/buy.
I've been reading a lot lately about the pitfalls of cronic cardio, try to avoid that. It leads to sore joints and boredom. Mix things up. My latest plan to mix things up is I plan on getting an archery set. Nothing fancy just work arm and chest muscles and have some fun shooting targets.
Cheat some too. Maybe as a reward for sticking to a planned exercise routine for a week. I like a full Mexican dinner when I cheat but whatever makes you happy. I'll also indulge in a little dark chocolate every now and then. Check the stores and go for the good stuff. There's all kinds of neat imported dark chocolates out there, buy the expensive stuff so you won't be tempted to eat it all the time.