If you look at the tables in the back of the manual you will see the hp you have
1d10
2d10
3d10
4d10
5d10
6d10
7d10
8d10
9d10
9d10+3
9d10+6
9d10+9
this means you start with a +1-10 hp per level + con bonus
after level 9 you get 3 hp added without bonus
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