First car's are always difficult, you've no real idea on what's what or even what you actually need.
I would hesitate buying new. Though the experience to start with will be great, you are wide open a lot of hassle that can cost you dear.
Claim for the smallest bump will see you paying the price for years to come via insurance premiums and you'll not want to leave a new one with a battle scar here and there.
You'll almost certainly have a big excess on a new driver policy, so in the event of a total loss, you would lose a massive chunk of the cars value.
You don't want a banger either.
A cars life to a manufacturer these days is around 7 years, after this it all starts to cost to keep it in good fettle, particularly now cars are more electronic and computerised.
So you want something cheapish but still current, with a low insurance group, with some form of warranty and perhaps help to start you off.
Plan on running it as cheaply as you can for 3 or 4 years and try not to worry about the odd self inflicted knock or bump.
So I suggest you start looking at cars coming off 3 or 4 year PCP deals at the main dealers as they'll be a good 4 or 5 years in them in the eyes of the dealer/manufacturer and most will only just be broken in with minimum miles on them.
They'll all be serviced on the dot and most niggles will have been sorted under the original warranty.
Look at base spec/engined cars and try and sniff out ones that may have had the odd option fitted, though it's not a deal breaker as things like aftermarket hands free systems can be added quite cheaply these days.
Go over it with a fine comb, anything like a rusty exhaust, worn tyre etc, get them to replace them and ask them to throw in a spacesaver spare too, push them so you're sure as can be there's a good few years in it without unnecessary spending, though don't get rude, the salesperson will hopefully be your first point of call for help and advise about the car, so you need them on your side.
Which car?
I wouldn't worry too much about it yet, worry later when your wallet and heart agree, but perhaps this very forum might be a factor in choosing a manufacturer.
There's no end of help for owners on here, most of us have been there and done it and know our way around various models.
Which leaves you perhaps a choice of:
500 Pop with a 1.2 engine
or
A Panda Pop with the same engine.
The 500 is a bit pricier, it's designed to be "designer", though underneath it's fairly solid and the running gear well proven.
The Panda's a bit more utilitarian, but has the same mechanicals.
It's a bit cheaper and a bit more sensible and practical, which helps with insurance.
We bought our lad a Panda Pop when he started out, now me, the mrs and him fight for it!
We bought it as above, straight off a PCP with 5,000 miles on the clock and it's cost us nothing except a service once a year.
It runs like a dream and we're not to bothered about the odd nic and dent, though we know as soon as his insurance drops, he'll see himself in a new Mini Cooper (and almost certainly a big write off!)