how to install vst plugin for cubase9.5

please let me know how install VST plugin for cubase9.5

Usually you will have an installer to take care of this but in some rare cases you will only have a dll or vst3 file. You can put this in a directory that is scanned by Cubase like C:\Program Files\VST Plugins or for vst3 C:\Program Files\Common Files\VST3