Specifically, the cell identifier includes a PCI and/or a CGI. The frequency information includes an SSB frequency (for example, absoluteFrequencySSB) of the candidate target cell and/or an absolute frequency position (for example, absoluteFrequencyPointA) of a reference resource block (common RBo) of the candidate target cell. The identifier of the first beam includes an SSB index and/or a CSI-RS index. The first random access channel RACH resource includes a first dedicated random access resource and/or a first common random access resource. The first dedicated random access resource is associated with the first beam, the first dedicated random access resource includes a first preamble index and a first time-frequency resource, and the first common random access resource includes a second time-frequency resource.