Is it permissible to repair some things in the house, such as the kitchen pipe and the water pump, instead of paying off the debt incurred from the increase in tuition fees, for fear of informing the father and his attempts to ruin the household?

If you took money from your father unjustly, you must return it or seek his forgiveness for it. If you are unable to inform him, you must return it whenever the money becomes available, and he does not necessarily need to know about the return. The principle for returning money is to do so in kind, unless the owner of the right consents otherwise. However, if your father is remiss in providing obligatory maintenance, then you are permitted to spend these funds on those maintenance expenses.