Alison online course

Is it worth me doing a free alison online course just for something extra to put on my personal statement or is that useless??? bare in mind i have no outside experience in the subject course i want to study...

Most of the courses that I have found on the platform are not accredited professionally by any body or regulation. A lot of the material on the platform are also aimed at GCSE sort of level.
As far as I know, none of the material on the platform is taught by academics, so it doesn't seem to add much value.

By all means do them should you wish, but I doubt they would help that much. The better platforms in my opinion are Great Courses Plus, edX, Coursera, amd Future Learn - these should be taught by academics.

If you can be more specific about the subject that you want to study, I can try to be a bit more precise with recommendations.

thank you, i am looking into economics/ finance related courses

If you are intending to go into economics/finance, then chances are you won't find anything on Alison.

As per above, Great Courses Plus, edX, Coursera, and Future Learn are the better platforms for what you are looking for. Udemy is also a good platform since some of the courses are taught by specific professors, but the platform itself is a bit mixed so I would stick to the previously mentioned platofrms.

Just out of interest, why a degree in finance? Do you intend to go into the finance industry? If so, then a professional finance qualification is oftentimes a better alternative to getting into the industry than a finance degree (because the professional qualification will definitely cover the laws and regulations required for the specific role that you want to do whereas the finance degree only covers the finance theory).
Having said that, a professional finance qualification won't generally help your uni application because the course material is so different to what's in the degree. Unless it's something like AAT for accounting degrees, usually finance qualifications are not asked for by unis (they will be asked for by employers though).

There is usually a large plethora of books on finance and economics that you can refer to, and they oftentimes can be sufficient to get into most unis. If you want to look up which books are recommended, you can usually google for economics/finance + "recommended reading list"; there are roughly around 5 unis that publish such lists for either finance or economic degrees at their unis.