This is going to be long!!!
You can try contacting the hotel about which apartment you get. There are 7 blocks, block S1 is the closest to the rest of the resort and overlooks the golf club pool (which is heated and good for kids), although I'd guess a ground floor apt there would have very little view as it's sort of screened off by trees IIRC. Block S7 is absolutely miles away and will be a serious hike. In the middle is the Residence pool. You can see the resort layout here : Pine Cliffs Resort Plan
Pool and beach towels are provided - you get towel cards which you swap for 1 or 2 towels each time, and return them when you're finished with them, so that saves you lugging them around.
Re coffee/tea etc, it depends if you're getting a "welcome pack" with your booking. We get it, as well as some fruit and milk, orange juice etc, because we own a week at the Golf Suites (marked C on the map), but I expect some agencies like Cadogan or whoever might offer the pack too. Unfortunately the mini-market just outside the main gates has been closed for a while, although there was a sign indicating it might reopen, so the nearest place to buy reasonably priced groceries is a 5-ish min walk as you turn right out of the main gates, along the main road and on the left side of the road. If you're hiring a car you'll be able to find a bigger supermarket and stock up, and also not collapse from heat exhaustion when carrying it back! SuperBock is good beer (lager) or Sagres Bohemia ia a darker ale-type beer. Yum!
The prices of things in the resort are ridiculous - 3 of 4 euros for a scoop of ice cream at the beach bar, can of coke for 2 or 3 euros - I can't remember exactly because we obviously didn't DREAM of paying it! We just got supplies from the shop outside and took them down to the beach with us. There are sunbeds with shades at the beach, but there's obviously a limited number.
6/7 yrs old is a bit tricky - DS is 7, and he was too big to use a lot of the kids stuff such as scooters, trikes, bouncy castle etc, which is free to access in the Porto Pirata area. There's a not terribly well maintained mini-golf, which costs 5 euros each (!) but was 25 euros last year for a weeks' pass for 2, so that was better value. This year the weather was great so we didn't play, but last year it was dodgy so we played loads and got our moneys worth. The TVs have BBC1 and 2, and CBBC, CBeebies and Cartoon Network, as well as the usual suspects of Sky News etc, so that's good for a bit of cooling down time indoors. I'm not sure if there are DVD players in the Residences - we have to pay 10 euros a DAY to hire them in the golf suites, needless to say we don't bother! There's a games room with various machines in, but we didn't look in there, and there are activities for older kids but they're all paid for via vouchers and I don't know how much.
Ummm... Oh, there are lots of frogs in and around the stream running through the grounds (the area called Pine Cliffs Village on the map), which can be fun to spot of an evening before going out to eat. If you're not self catering I can highly recommend Adega ti Costa, which is opposite the hotel main entrance if you walk up the left hand side of the drive. It's not posh, but the food's good and they're really friendly, loads of locals in there as well as holidaymakers. They open at 7pm.
At the risk of sounding like a broken record if you check my previous posts, if you do sit through the Pine Cliffs Vacation Club sales spiel (and you get about 30 euros to spend in the resort as a reward I think, so not too bad) DON'T even THINK about buying anything without checking prices etc on the internet - Gold weeks (any time except Jul/Aug) in the Golf suites (Pine Cliffs Vacation Club, the blocks marked C on the map) are being sold for 29k euros by Pine Cliffs, but you can get a resale from the internet (and indeed from my good self!!!) for 10-15k, easily.
Phew!
I hope this helps! Have a lovely time, it is a fabulous resort, once you get over the prices!