My first gun was a Marlin model 60.
Then a Winchester Model 94 in 30-30.
I didn't fire a shotgun until I was 12 years old - and then it was a Remington 870.

Fast forward to recently and here's what I got my kids.

My son started with a Cricket .22
He later moved up to other .22, most recently a Savage bold-action .22 (I don't recall the model).
My daughter will start with the .22

For an adult starting out, I'd say any Mossberg 500 series shotgun is a really nice choice.

I'd not recommend a handgun for a "first gun" for anyone unless you're going to spend some quality time with professional training.

I know that handguns are much harder for me than long arms, so I might be just putting my issues on someone.

I have found that first-time gun handlers I've seen have done well with HK P7, S&W SP101, and any Glock.

But anyway, this is a topic that comes around here now and then, love to read these threads - so many good ideas.