Server-side and Client-side Help Needed!

I was creating a mod that reflected hypixel skyblock's minions. I was making a script that prints out a random number, and also posts it to chat. The issue is, is that it runs this script on the server side and client (Render) side, and so it gives me two different outputs.

Preferably, I would want the output to only have one, and I am a bit confused on how to solve it.

Here is the link to the file if nessasary: https://drive.google.com/file/d/16bMo1EsW764U-ul-dj_GnR2U1ospLx10/view?…

Thank you in advance for your feedback!