Q.Which Type Of Grass?
I live in Bordeaux France, a warm climate in the summer 30°C for most of July ans August but in mid winter is can freeze 0°C. The garden is 60m2 and has a 180m (6ft) wall around it but it faces south so light isn’t a problem. (Unfortunately) There is a large pine tree in the middle over 10m tall(too exppensive to cut down). The lawn area isn’t particularly flat which means i can over cut the grass in some areas very easily. The soil is sandy and some areas drain very quickly while others hold some water. I don’t have any details on acidicy of the soil.I am unsure whether the tree roots affect the drainage for the grass growth. And I have 2 toddlers and their friends who want to play. the lawn is patchy and I need to reseed. What is the best grass type/ seed for my lawn? Or what other information do you need to give advice?

Certified GKH Gardening Expert
Your area is most equivalent to our USDA zone 9. The problem that you will run into will be that the pine tree will prevent most grasses from growing in the area.
Unless the tree is removed, completely, you will expect very little to grow around it.
This article will give you advice on the best grasses that can survive in your climate:
https://www.gardeningknowhow.com/garden-how-to/gardening-by-zone/zone-9-10-11/zone-9-lawn-grass.htm