So sit with DH and a sheet of paper, and think about meals you all like and eat. Divide that into: need to prepare fresh, can be prepped ahead, good for bulk cooking and freezing.
Bulk cooking - start small. Say you are making a spaghetti bolognaise sauce for tonight - make a double batch instead and freeze the second portion for another night next week. So its just reheat sauce and cook pasta - mostly ignoring cooker for the 15 mins involved. An extra 12-13 mins to do something else.
Prep ahead ones mean peeling and chopping vegetables, maybe making a sauce, maybe putting together a lasagna or shepherd's pie or something - and just cooking that the following day. I love doing small midweek roasts or lasagnas or pies that I can set the oven to cook and it's just done as we walk in the door from work. It's great if you have that function on the oven. But even being able to just turn on the pots - either to ignore once boiled (give the occasional stir) or to start cooking a stirfry type meal straight away rather than chopping etc first, makes a big difference.
And when I said to think about 2 days of shopping today, that was only to take a small bite of the elephant. If you reduce the shopping to every 2nd day, that will free up more time. But using the list above should help you to think about what you might eat for 3-4 days, or even a whole week, ahead of time. And only need to go shopping once a week - and maybe even the odd week doing a big shop on the internet to get the bulk items (pasta, rice, baking ingredients, cleaning items, cereals, etc) for a few weeks and you only have to get milk and dairy, meat/fish, fruit and veggies, in between.
But - eat the elephant in small bites and don't try to run before you can walk!
Exercise - combining play - go for a "nature walk" every couple of weeks, a swim some afternoons, or just running around playing "chase" with your DD. They will all help to build up your exercise minutes.
I put paperwork/post with the diary on the high part of the kitchen counter, and deal with everything after dinner most days. So bills to pay, school notes, reminders to make appointments or whatever. But I don't deal with it as I get the post and arrive in the door (I only get home at 6pm, so dinner and feeding the roaring dinosaur (aka 10 yr old!) are priorities).
Get the 4 yr old to help with some chores. For example, she may not be able to ball up socks, but she could put them into pairs for you to ball up much quicker. Make it a game. Get her to fetch ingredients as you start dinners, and even teach her the bits she can help with - stand her up at the kitchen counter, give her an apron and let her get stuck in. She can do the small brush and pan part of sweeping the floor, after you do the big brush making the pile of dirt in 1 place. Teach her how to set the table - starting with helping get the dishes and cutlery out but move on to fully laying them out. And to help clearing/washing up. It may all take longer, certainly initially, but she'll learn valuable skills and you are still having quality time together. (And washing up is so much fun with all those suds and splashing!!).
Cards drawer is invaluable. Especially a stock of age cards in the same age range as DD and 1 year ahead, and non-age child birthday and non-age adult birthday ones, but also anniversaries, get well soon, mass cards, acceptances/rejections for invites (probably mostly adult invites) and thank you notelets. If you have the budget for it, head to a toy store one night when you have the headspace, and buy a bunch of nice toys for class parties (board games, jigsaws, generic lego sets etc), and see if there are good solutions for family birthdays etc coming up in the next month or 2 as well to pick up. Lay in a small stock of nice smellies or some nice candles or nice mugs and select teas/coffees for adult presents, or a nice beer mug and craft beer for gents. If you can, try to do this in sales (post Christmas and summer sales tend to be best, but there are so many sales these days!). And if you are addicted to the internet, use that and do some online purchasing so you can get some really interesting things for the same price. Only buy though what you would be happy to give - try to have some idea of the people you are buying for and then lay their specific things aside for when they're needed. But have a few more generic presents available too, for last minute invites or ones that slipped through the diary.
I also use a notebook, to make lists of things I need to get (some are urgent, others I spot that need replacing or the event is a while away yet) - but they are all there when I am out shopping or browsing. And other lists in there of things coming up, or other jobs that need doing.
DH and I also tend to do a blitz of the cleaning once a week - and we are seriously contemplating getting a cleaning service back in again once a fortnight for the heavy stuff. But we spend an hour or so doing the bathrooms, sweeping floors, hoovering, changing sheets and towels, mop floors if needed etc. We tend to keep the kitchen tidy as we go and pick up clutter every night (and sweep kitchen/diner floor most nights too). We organize the laundry by pre-setting the machine (late in the evening) to turn on while we're out next day, and it's done when we get in at 6 - if weather is good, it goes on the line while dinner is cooking; if not, the dryer goes on then while noisy things are happening rather than later when we want to sit and relax. And we fold it ALL on a Saturday/Sunday evening while watching tv, so it actually isn't a dreadful task then.
Sorry, I'll shut up now, unintentional lecture over....