Is it permissible to give charity on behalf of the deceased with money, and is there a better way to give charity on their behalf?

If your father bequeathed two camels as charity and their value does not exceed one-third of his wealth, then the bequest is valid and must be executed before the division of the inheritance. If it exceeds one-third, then whatever the adult, mature heirs approve is valid; otherwise, only up to one-third of it should be executed.

The bequest must be carried out exactly as the deceased willed it, without change or substitution.

If your father did not leave any wealth, you are not obligated to give charity on his behalf, but it is better to do so. Dedicating the reward of charity to the deceased reaches them and benefits them.