Is it permissible to give bank interest to a parent who is unable to work, or to the poor?

It is not permissible to deposit money in interest-based (riba-based) banks except out of necessity or extreme need, as doing so constitutes assistance in sin. If one is compelled to deposit money, they should take the interest and dispose of it by spending it on charitable causes for the poor and the like, and not benefit from it themselves or for those whose maintenance is obligatory upon them.