When picking up advice from the web it's always important to know the commercial interests of those giving it. Particularly on investment matters.
The UK Shareholders Association (UKSA) is a private organisation that promotes the importance of individual shareholders, conducts periodic campaigns to correct specific injustices, has growing influence and deserves support. It is independent of all conflicts of interest and funded entirely by membership fees and individual donations.
Sharesoc is a sister organisation of UKSA, with a greater focus on the skilled private investor and active campaigning on specific corporate misdemeanours.
Government bodies have a number of different advice services of varying quality, due to be consolidated into a single service in 2020 under the name 'Money and Pensions Advice'. Currently the most relevant sites are Money Advice Service and Pensions Advisory Service. Remember that no government advice site is going to upset an industry that contributes 15% of national tax revenues, but with that proviso they do their best.
HM Revenue and Customs (HMRC) is the horse's mouth for any tax regulations.
Martin Lewis at MoneySavingExpert has the pre-eminent independent site covering basic money management skills, with much practical advice and information.
Boring Money is a very approachable site with an individual style derived from its founder, Holly Mackay. But its independence must be questioned since it took on a group of 'expert advisers' headed by two very senior managers from Hargreaves Lansdown.
Recommended books and other sources can be found at the end of the Advanced Investing module in More Advanced