assalamu alaikum sister
congratulations on accepting Islam, may Allah Most High continue to bless you and guide you and keep you and me on the straight path always ameen.
If you are in the UK, whereabouts do you live?
It is difficult to tell family members especially if they are active practising Christians. It's fairly likely that they will freak out, I'm afraid, given most peoples false ideas about this deen. Did they know you were investigating Islam?
I advise you first and foremost to pray the 5 daily prayers and stick to them as if your life depended on it.
