Greetings Kate,
It sounds like you plan on being a safe driver, not the type to abuse the power and mash on the throttle. A Porsche absolutely can be driven safely of course, such as the 911. The base models don't have an insane amount of power, are still spicy and can still get you in trouble if you want to, but for someone who wishes to drive it like a sane human being, it can of course be done very easily.
The problem is that a lot of people say they're going to drive a car like this safely and tamely but when push comes to shove it is really really hard NOT to drive a purpose built car like a 911 and want to drive it fast. All it takes is one time of bad throttle control around a corner and things go sour very quickly in a car like a 911.
I drive older Porsches, so my 911 isn't crazy powerful (just a tad over 200hp) but of course, if I wanted to go fast it will still go fast. Whether or not I do that is my choice to put my foot down and risk getting a ticket. I don't find it anything crazy in the rain or the snow (contrary to popular belief). In fact, with a good set of tires, it's actually very good in the snow and in the rain and is an all around fantastic daily driver. The problem is that with all the weight in the back, once the end starts to come around, if you are not very quick to act, your face is where your butt was a few seconds prior.
I've only driven a handful of watercooled 911 models, never anything on the crazy side of the spectrum, but they were definitely tame if you wanted them to be.
I think overall for someone who has a tendency to abuse the power of a car, I would say absolutely not. For someone who just wants to get from A to B in style and can exercise self control, sure, you definitely could. Recommended? Well, not necessarily since the power can get you in trouble if you decide to go bonkers and try it out and aren't ready for it. But it really depends on the person.
For a first time driver, I wouldn't recommend it. No one can really stop you from making that decision. I'd say no for the most part. But if you really TRULY can exercise self control, maybe. I have to agree on the majority of the no answers here though as they've made very good points.