Mọi người giúp em với ạ, em làm mãi mà không sửa được lỗi, thank

PS C:\Users\chibi> hello.py
hello.py : The term 'hello.py' is not recognized as the name of a cmdlet, function, script file, or operable program.
Check the spelling of the name, or if a path was included, verify that the path is correct and try again.
At line:1 char:1
+ hello.py
+ ~~~~~~~~
    + CategoryInfo          : ObjectNotFound: (hello.py:String) [], CommandNotFoundException
    + FullyQualifiedErrorId : CommandNotFoundException