As far as I know, the PGDL isn’t eligible for a post grad loan. The PGDL can be included in a masters and the BPC can be upgraded to a masters, so presumably loans available for those.
I can only speak of the barrister route: it’s an expensive process but fees are actually less than when DD qualified some 8 years ago! For barristers, the Inns of Court have scholarship funding or bursary funding for the PGDL. Otherwise it’s £10,000 ish for fees and more in London. Some DC work on the days not in college. Or start volunteering ! Living at home obviously helps with living costs.
I would say always do the first degree in a subject you really really want to do. My DD did MFLs. Other friends of hers have done History, Classics, History and French, Music and probably quite a few more I’m not aware of. They have all been to very good universities and often Oxbridge.
After PGDL it’s the BPC. Barristers apply for pupillage prior to BPC or after. Depends whether they are doing a masters or other law experience before starting pupillage. If they don’t get pupillage, they have to keep trying!
The inns of court have generous scholarships for the BPC covering all the fees or a good chunk of them - but they are competitive. A scholarship is brilliant to have on the cv. I know there are also residential scholarships at the Inns to assist with living costs. The 1 year BPC will be around £15,500. DDs was more all those years ago. Too many people take it and many never get to be barristers. Keeps the costs down I guess! Pupillage awards can often be drawn down to pay for BPC too, if they are a good sum of money.
So choose the route that suits best. Not everyone is suited to a law undergrad and plenty of exceptional people don’t have it.
It’s vital to get a zinging cv. Seeking pupillage is highly competitive and it’s not for the faint hearted. There are huge numbers of deadlines all the way through the process, starting at university, so young people must be organised and dedicated. However DD loves it but it’s vital to know what area of law you are best suited to and the best route into it.
Anyone loving law should do law at university but do another degree if there’s a compelling reason to do so.