Is it permissible for a 15 year old convert that is dependent on his islamophobic parents to lie about being Muslim if his parents have beaten him in the past for it?
We make du’a that Allah Ta’ala keep you safe and provide you safety from any ill conditions, Ameen.
Considering your situation, it will be permissible for you to keep the information about your conversion to Islam from your parents. Moreover, you should work towards finding independence for your living arrangements. However, if that is not yet feasible, try to maintain your Islam as much as possible without putting yourself into any jeopardy.
And Allah Ta’āla Knows Best
Mufti Faisal al-Mahmudi