Audio Mixer and iPhone setup for podcast/YouTube videos?

I'm looking at starting a podcast/YouTube channel. I will be conducting interviews so will need 2 mics minimum. I'm going to be using just my phone for now to record the video however I'm a bit stuck on the audio. Can I hook up my iPhone to an audio mixer and then hook the mics into the mixer to record audio and video that way? If so, do I need some sort of adapter to go from the mixer to my phone? I'm new to all this and just want to make sure I'm doing it correctly!

My iPhone 7 screen is on but it is black?

Today I accidentally dropped my iPhone 7 Plus in water. When I took it out, the LCD was on but the screen was black. This isn't the common issue where the screen is completely black and the LCD is off. The LCD is on, but it is black. I can still charge my phone and it still vibrates, and can even respond to taps when I try to unlock it, but I've tried to hard reset it, charge it, turn it off for a while, and it still doesn't work. Any knowledge on this kind of damage?

WHY DOESN't GMAIL WORK ON MY IPHONE 📱?

On my iPhone 8 Plus my Gmail literally doesn't work, what I mean by that is I don't get any emails on it! Nothing shows at all. On my tablet the gmail works and I can see all my emails I literally don't understand why I'm not receiving any emails on my iPhone. It just saids "NO MAIL" but I know I do have mail I see it on my tablet

Which iPhone should I get? - 4

I currently use the 5s but i plan to upgrade it soon. Should I get the iPhone XS Max or wait for the iPhone XI? What do you think?

Whacky phone service or something else?

And the person I'm trying to talk with has an iPhone as well. For the last five or six days, whenever I send an iMessage, it goes to SMS after a couple minutes and the entire messaging platform doesn't revert back to iMessage for about a day and a half.

Calling the number elicits weird responses. Usually, there will be half of a ring and then it will tell me that the person has a voicemail box that isn't set up, and from there it immediately goes to that message without ringing if I call again.

Using *67 allows the number to ring fully, however, sometimes calling without *67 also allows the number to ring fully as well, though this is often late into the night.

Is their phone or mine behaving out of whack? Are there any remedies for this?

Is the iphone 8 too big?

I'm getting my first phone i don't know what kind to get i don't want to big of a phone like the 10 xr would this be ok or a 7 or a 9?