Anyway, with a student loan, after you graduate, if you are a PAYE worked earning above the threshold, you will make repayments towards your student loan "debt" equal to a % of your income, which is deducted automatically from your earnings each month like (and alongside) income tax, NI contributions etc. The amount will depend on your income and if you are earning near the threshold you will repay very little and so no matter what, you won't "miss" those earnings really except in abstract terms. It is essentially just a graduate tax in all but name. If you earn below the threshold (either in total, or in a given month) you won't make any repayments. Your student loan "debt" will continue accruing interest each year however, whether you are making repayments or not.
The reason I use the quotations marks around debt is because, in practice it's not like real debt. It doesn't affect your credit score, and unless you leave the country without notifying SLC (the Student Loans Company, which is the company that gives out the loans you apply to Student Finance England for), or are a self-employed worker and misreport your earnings, you will never have bailiffs banging down your door for student loan repayments. For most salaried workers it's not even something you need to think about (other than maybe sometimes looking at your monthly payslip and groaning that this month you repaid £10 or £50 or £200 or if you're an investment banker or something maybe even £500 towards your student loans that you could've used to buy X other thing).
So if you are earning just at or over the threshold, for the rest of your life, then you would be making small repayments until you retire, probably never paying off the entire sum, and possibly repaying more than you borrowed. However, because the repayments are such a small proportion of your income, and because it is proportional, it probably won't make a difference in your life either way. If you are earning significantly more, you will repay more each month, but again, since you would be earning so much then you likely won't miss the relatively smaller amount. Additionally, once you hit retirement age (or if you earn under the threshold for a set number of years) the remaining loan is written off anyway.
Essentially then, if you don't need to take out the loan there is really no benefit in doing so considering that action in isolation. Equally there is no particular downside, and you can potentially do a lot more with the lump sum funds used to pay tuition fees each year that might in fact generate money long term (e.g. using it as a deposit to purchase property). So it's really up to you and your parents. If they have that much money available to them, I would suggest a more prudent investment would be for them (or you, with that money) to purchase some property and rent it out while you are in uni and then have an owned home when you finish your degree (which you can then continue renting out, or sell it if doing so would be profitable, or indeed live there yourself). Alternately if your parents are interested they can pay my tuition fees for me