is your personal hotspot secure?

Hotspot or otherwise. I am not sure what exactly you mean by "Secure"

iPhones cannot be hacked or infected with Virus / Malware / Spyware by merely clicking on a link in Safari, unless you have intentionally downloaded spurious softwares or unauthorised apps directly from internet and installed on your iPhone or/and have Jail Broken.

You need to look at the way you share your sensitive and valuable informations of your device with your friends and family members.