Yes another chiming in to say you'll make far more contacts if you use FB. MN is notoriously sceptical of Home Ed so you need a platform that gives you the most opportunities to find groups and resources for HE.
I only use FB for groups nowadays and it's the reason I won't leave FB. It is utterly invaluable for groups. As well as the HEFA group mentioned above, there are numerous local groups and also groups focusing on more specific advice on individual subjects or types of HE (unstructured/structured/Unschooling etc) and recommended tutors etc.
When our children were your children's age, the FB groups were in their infancy. Back then Yahoo groups were a thing and that's how I discovered my local group!
As for tutors, you really don't need them at the age your DC currently are unless you particularly want to splash out. We were very unstructured which we don't regret at all. We focused on play based learning and letting children explore their natural curiosity. We never forced anything and as soon as they got bored, we changed path... Boredom = switched off! We learnt that the hard way!
We did use the Reading Eggs app which they enjoyed and a maths one but most maths at that age was real life maths... Talking about pricing in the supermarket, weighing ingredients etc. They learnt a lot more when it was fun and exciting.
We couldn't be more glad we home educated our children. They both got a full set of GCSEs and now one is mid A levels and the other is on her gap year after getting three As at A level. We really feel their drive and enthusiasm for the latter years of their education was borne from a very child led, unstructured approach they had when they were young.
Hope that helps and good luck!!