For Mac I'm following how to download it but it doesn't work

I followed what this said "https://support.logmeininc.com/pro/help/on-my-mac-logmein-hamachi-wont-start-when-i-press-the-power-button-what-can-i-do" 

But the thing about that it doesn't working once I get to step 3 "Click Allow next to System software from developer "LogMeIn, Inc." was blocked from loading."

there's no allow button neither a text for it