Something has hacked calendar on my phone. I went to calendar accounts and deleted the rouge account as you can see. Do I need to do anything else? Has my phone been hacked? Is my personal stuff safe?

personally (on my iPhone), no.. I have not seen this.

I have certainly seen others post about this on these forums and I direct them to the following link to look at Axel's response, but it sounded like you had already figured out how to remove it

Calendar Spam Removal - Apple Community

well you should understand that this is a user to user forum.. I am just another iPhone user like yourself.

There is no way I can personally guarantee that your personal info is safe. Just based on what I understand this is adware that gets into your calendar.. probably from something that you clicked on while browsing

If you are worried about security of your data, I would be making sure that you can answer yes to the following questions more than I'd be worried about a rogue calendar that was able to be deleted. (again this is my opinion)

Do you lock your iPhone with a passcode? If not, you definitely should. More characters is more secure.

Do you have 2 factor authentication turned on? If not, you should

Do you have find my iPhone turned on? If not, you should

Associated articles below.

Use a passcode with your iPhone, iPad, or iPod touch - Apple Support

Two-factor authentication for Apple ID - Apple Support

Set up Find My on your iPhone, Mac, AirPods, or other devices - Apple Support

you could take it another step further.. (I don't think this is necessary, but if it makes you sleep better at night?)

Check your Apple ID device list to see where you're signed in - Apple Support

If you think your Apple ID has been compromised - Apple Support

Change your Apple ID password - Apple Support

Also, do you use iCloud Keychain to manage your passwords? I think it's nice because it will help generate complex passwords and it'll remember and auto-fill them for you (assuming the app and/or website is coded correctly to utilize it)

What this can also do for you is review your passwords. It will warn you if you are using the same password for multiple accounts and will also let you know if your password was found on any databases due to breaches.

Set up iCloud Keychain - Apple Support

your iPhone was not hacked. Sounds like you found the issue and deleted it. You should not need to worry about your personal info.