If you are employed by the takeaway, then as you are in the UK, you are covered by minimum wage legislation. Your employer should be paying you the costs of doing the deliveries, plus the national minimum wage (which varies by age). If they're not, you should demand this - which may in practice result in you losing your job, but either way you'll be owed back pay for the difference.
There's a possibility you are actually "self-employed", in which you have no recourse other than to leave as you are considered to be responsible for yourself. However, it's very tempting for businesses to classify people as self-employed when they're not, and you can challenge that status - there have been some well-publicised court cases about this, for example this one. You can read the definition of self-employed here. I think you could probably point to not getting to keep tips as one piece of evidence that you aren't self-employed. If you're paid hourly rather than by the delivery I think that would also strengthen your case.
If you are employed, have a look at
https://checkyourpay.campaign.gov.uk/#is_your_employer_paying_you_properly_ for more information on your rights.
As mentioned on that page, you can also talk to ACAS or report them directly to HMRC, anonymously.
They may also be obliged to hand over your tips in addition to the minimum wage, but I'm not sure of the exact rules on that. For example it might be ok for your employer to collect them and share with the "non customer facing" staff like the cooks. There's some information about it here and it's another thing you can ask ACAS/HMRC about.
You have no direct rights to any delivery charge your employer charges customers, but of course they may use that to fund paying you your wages and expenses.