TLDR version:
Stay away. This bike will need a lot of work. It's worth probably £100 - £150 for someone to run it into the ground as a commuter. It will cost another £200+ in parts and labour to get it working even close to minimum viable condition, and that's assuming nothing is broken on it that we can't see.
Longer version:
It would be a great start into road biking if it was in great condition. An aluminium Specialized with Sora is about bang on the money! But sadly this bike looks in terrible condition. Note that this is the 2013 model, not the 2021. If you aren't experienced in knowing what to look for then buying off a definite liar is a problematic start!
(see below to see the colourway in action)
View: https://www.amazon.co.uk/Allez-Sport-2013-Silver-Specialized/dp/B00DQZC7YS
The drivetrain condition is vomit inducing. It's basically being lubricated by road gunk at this point, and likely has been like that for many years.
I'd say there is about a 100% chance you'll need to chuck the chain away, a 99% chance you need to chuck the cassette away, and realistically a 90% you should bin the crank cogs too (these matter less so you could get away with it... maybe)
Given it has been maintained so poorly the likelihood is you'll need to change all the gear cables too as the friction built up will ensure that you'll never get a smooth shift unless you do. I'd also change brake cables too, because safety an all that!
So £15 chain, £25 cassette, £20 cables / casing, you're already adding £60 on and that's without labour, and just sticking with the probably messed up crank cogs! Another £30-70 for cranks, or just cogs for the cranks, and probably £20 for a bottom bracket? And you won't want to fit that stuff yourself, so it's likely £50-£70 laboutr at an LBS.
This is just stuff we can see. You may find play in the headset, the bottom bracket, the braking surface on the wheels may be worn, the tyres may be beyond useful life. These things are a risk with any bike though so before buying make sure you learn how to look for these things (GCN did a good second hand buying guide about 5 years ago, definitely watch that before buying anything too and go to any second hand purchase with a checklist of checks to arm yourself with).
If you look on
https://www.bicyclebluebook.com/value-guide/product/3045025/
it suggests $219 - $360 depending on if it's broken and in need of parts, up to immaculate condition. (don't worry that the picture is blue, it's the same bike, look at the design patterns)
I'd put this one right at the bottom of that. So maybe £150? (and this is far worse value than one in excellent condition for £250... which I would advise as a great option!!!)
I would consider this bike for £150 if I wanted a commuter. I'd just clean up the drivetrain and leave all the rubbish parts on it (maybe just change chain and casette). It won't feel great, and shifting will irritate, and nothing will feel good, but this is what I want in a commuter. something I won't feel too sad about if it gets stolen!
I wouldn't advise it as something to start a road cycling journey as a hobby, it's just too far away from minimum acceptable condition.