Malware access to iphone camera

iOS / iPadOS devices cannot be hacked or infected with Virus / Malware / Spyware, unless you have intentionally downloaded spurious softwares or unauthorised apps directly from internet and installed on your device or/and have Jail Broken. 

It also depends on how careful are you in sharing sensitive and valuable informations of your iPhone such as Passcode, Password etc with your friends and family members.

It could be Phishing

• Beware of --> Phishing & Other Suspicious Emails 
• Know how to --> Identify legitimate emails from the App Store or iTunes Store 
• Avoid phishing emails, fake 'virus' alerts, phony support calls, and other scams —> Use these tips to avoid scams and learn what to do if you think your Apple ID has been compromised.

I had something similar. I was supposed to send bitcoin to somewhere or they were going to share video with all my contacts. I didn't send anything. no reply. no bitcoin. as far as I know, no contacts got any video (or they're all too polite to tell me).

I thought that was sort of the end of it. But once last night, and then again this morning, when I wasn't talking on my phone with anyone, but was browsing on my phone, i thought that someone said just a short sentence to me. it wasn't very loud. Is this even possible? Now I've been going through my emails and have once from yahoo that says a sign in attempt was made: This sign in attempt was made on Device: chrome, windows nt when: April 23, 2020 5:32:41 AM PDT Where: Vietnam 113.190.32.131. At that same time, I was getting messages on my phone requesting the password for this particular yahoo account. I got that request maybe 6 times in one minute.

I had a similar situation, I clicked on a website that I thought it was trustworthy and instead it lead me to a page that had a note saying that this was a virus and I had been infected. I closed safari straight away and erased all of my website information. I didnt provide any personal information or purposefully download anything. Can I be assured that there isn't anything suspicious on my phone? Thanks!!!

I also received this email this morning, requesting money or they would send a recording of me to contacts.

what did you end up doing? Presumably no recording was sent to your contacts?

As with all such emails, it is a scam. Simply delete the email and move on with your day.