keep getting this pop up saying TechSignalDaemon will damage your computer how do I get it to stop!

Try to remove this by following the simple steps provided below: 

1. Check your System Preferences if there is a created Profile. 

Note: If you don't remember setting up any profiles for your mac, we would advise to remove these created profile. 

1. Click on Profiles and it will open the list of configuration then you may delete all of them. 
2. After removing all the configuration profile, it will ask you for your password to allow the changes. Type it in. 
3. Please try to restart your mac. 
4. After the restart, check your Safari's preferences if you can now modify its default settings and check if the adware still exists. 

Hope it helps!