First trip to Center Parcs - Hit me with you tips!

[ChocolateChipMuffin2016]

As the title says, we're going on our first trip to Center Parcs in November and I am looking for any tips or tricks you have to make it easier (cheaper) for us.
We are going to Woburn Forest with family, 11 people consisting of 2 couples and 2 families (1 of 4 and us; me, DH and DS aged 2) sharing 2 lodges. Kids are between 2 and 6 months, so young! Some of the others we are going with have been before but aren't being massively forthcoming about how it works and me and DH feel a bit stupid not having a clue.
Some of our questions are: is it all indoors? Do people generally have the activities you can book on every day? It seems like it could be very expensive if so. Are there other things to do, other than walk around and use the pool? My DH was wondering if you can go off site or are you trapped once you get in ?
Anythings you would definitely do/take/avoid? Any hints for keeping the small people entertained?
Sorry for all the questions, but it's our first holiday in 3 years and we want to try and make the most of it! Thank you!

Re insurance, it is always advisable to have travel insurance whether holiday is in UK or abroad. I think most travel policies include UK breaks over 2 days.

We have never been to Woburn, but have regularly been to Longleat since DS was a toddler, now a teen. It is his favourite holiday, although we have noticed it is getting more and more expensive.

As others have said as the DC are very young, just being there will be exciting especially if they see any animals/birds coming up to the lodge. Last time we went we had to shoo ducks out of the actual lodge! Definitely take bird food.

We took bikes the first few times but in the end decided it was easier walking/getting the land train (don't know whether Woburn has one of those) Longleat is also very hilly.

When DS was little there was a Teddy Bears' picnic activity which he loved. If there is a craft session on last day, ensure it doesn't involve glitter. You will end up with glitter everywhere (bitter experience)

We always pack our swimming stuff separately, so can make use of the swimming pool before we can use the lodge. Can also do the same on the last day, once you have checked out. But the pool can get busy. Longleat has a great toddler/baby area in the pool, don't know whether Woburn has the same.

You’ll have a fab time, we went last Nov with friends, the children 6m-4years.
The indoor pool is fantastic & there is an indoor soft play(not massive but no extra charge). We did pony ride, bug hunt, owl experience, Messy Play & boat ride which we booked before we went. Some days we did pool twice a day.
Took the scooters for the children and there are two outdoor play areas.
We only ate out once at the Pancake house. We had a big online shop to take with us & then shared the cooking so spent very little extra in the onsite supermarket (more expensive than regular shop but has everything you need).

Have a fab time