You can create a platform and import samples from GSE SOFT files.
However, GSE SOFT files of High-throughput sequencing data don't contain the data in it. In such cases, maybe you can download text files of Count data as Supplementary files. If not, you can get it from GREIN (GEO RNA-seq Experiments Interactive Navigator). And follow the tutorial "Import RNA-Seq Data (A Table of Counts / TPM / FPKM / RPKM)."
Or you can use SRA Toolkit to get FASTQ files to reanalyze from zero. But it takes a very long time, so you won't do it unless you have the inevitable reasons.