The use of the word "aim"

[Tom]

Hi

Could you please tell me if I want to use the word "aim" as a noun in the given situation, which verb I should use with it?

[Yankee]

Hi Tom

The phrase 'take aim' seems to fit your second sentence best:

2- He held his gun up and took aim at the lion.

You could also say something such as this:

His aim couldn't have been better; he downed the lion with a single shot.