1. A session establishment method implemented by an access and mobility management function (AMF) entity, the method comprising:receiving, from a terminal, a first message comprising first network slice selection information, second network slice selection information, and information for requesting to establish a protocol data unit (PDU) session;
determining a first session management control function (SMF) entity in a visited public land mobile network (VPLMN) based on the first network slice selection information;
determining a second SMF entity in a home public land mobile network (HPLMN) based on the second network slice selection information; and
sending a second message to the terminal, wherein the second message comprises PDU session establishment accept information.