Hi Mummy2008,
Yes, for P1 you have to buy all the textbooks listed, except for the MT subjects that your child is not taking of course
and those that are listed optional. Under the stationery list, you have to buy all the compulsory items. Unless you have them already, like drawing block and glue stick etc. But the exercise books will be necessary so buy according to the quantity recommended.
Chinese textbooks won't be ready till Dec, but I suspect it will only be ready after school reopens. This is due to the change in syllabus. Happened before to my P3 girl when they made some revision to the chinese textbooks last year. But you can check with Popular if you are near to one, they stock the textbooks too.