依法履行职能 meaning in English

perform duties according to law
perform functions according to law

We should uphold and improve the system of people ' s congresses and ensure that the congresses and their standing committees exercise their functions according to law and that their legislation and policy decisions better embody the people ' s will
坚持和完善人民代表大会制度，保证人民代表大会及其常委会依法履行职能，保证立法和决策更好地体现人民的意志。