OpenBVE is a completely free, open-source train simulator. It does not have the JR East branding, but the community has created thousands of free "rolling stock" and "route" files mirroring JR East lines (like the Yamanote and Tokaido lines).
. This trial allows users to experience authentic train operation between Tokyo and Shinagawa on the Tōkaidō Line at no cost. Ways to Access the Simulator Free Trial Version Jr East Train Simulator Free Download
While the full experience is a paid product, there are official ways to access a of a trial version to test the realism before you commit to a purchase. How to Get the Official Free Trial OpenBVE is a completely free, open-source train simulator