I want to give animation order to multiple objects in a single script. How can i do?

I make little games to learn. I'm stuck somewhere. First of all I have a character. When my character presses the key, the opposite characters need to be animated, but how can I assign this function to multiple characters. for example: I check the character a and press E and it needs to enter an animation where I specify the characters a1, a2, a3, a4 but I don't know how to write them in one script. Can you help me? I'm sorry for my bad english.