I m due for paternity leaves and same months my probation period is getting over
Should i inform hr now or i can inform same month after probation period is over ? Can they increase my probation period if i inform them now?

Do you mean to say that your paternity leave will begin at the same time that your probationary period ends? How long is the probationary period? The company is permitted to take any adverse actions on account of you going on paternity leave. Please contact our office to discuss your entitlements and rights.