If I was you, go for uni.
As much as you may end up in debt, theres loads of financial help out there. You don't have to pay your student loan back until you're earning £21k +, and it gets written off after 30 years.
as for apprenticeships, i know a bunch of people who went for one because it was the easier way out, to earn and to do something that they enjoy. I know one person who absolutely loves her apprenticeship (because as she sits an exam, she goes up the pay scale and at 18 she's now earning £20k when she started on £10k) on the other hand i know 3 people at various car companies who absolutely hate it because they aren't treated fairly, doing more of an admin person or a secretary kind of job. they aren't taken seriously and they are stuck doing that for another three years. they do their job and come home bored asf. all of them wish they had stuck to a levels and gone to uni!
even if you don't get 300 points, theres always clearing! the majority of people last year that went to uni did so through the process of clearing, not by meeting their entry requirements! so theres hope for all!
even after all that, you could retake a year of a levels, or take a gap year and sort things out for yourself. ensure software development is definitely something you want to do (I did computing and HATED it!!) you could always get a part time job and figure out what you want to do. plus if you decided for an apprenticeship, you may already be too late to apply for starting in September this year?
hope this kinda helps!