if you are undergoing hammertoe correction only you will be able to walk immediately after surgery and generally only require a flat postoperative shoe- which straps on and looks like a sandal. It is however important to keep the operated foot elevated for most of the day during the first two weeks after surgery. This is to limit swelling which can be painful and potentially compromise wound healing.
Less severe hammer toes can be corrected with soft tissue corrections alone in which case no implants are used. You would generally transition into normal (flat shoes) between 4 and 6 weeks after surgery. More severe hammer toes require bony corrections and implants are frequently used to hold the bones in place while they heal in the correct position. The majority of the time thin wires are used which stick out the ends of the toes and are removed in clinic at 4- 6 weeks. Once the wires are out you can get back to regular shoes.
Good luck with you upcoming surgery.