We can able to expose grafana dashboards to external world without login by setting below variables in grafan.ini file.
# set cookie SameSite attribute. defaults to `lax`. can be set to "lax", "strict", "none" and "disabled"
cookie_samesite = none
# set to true if you want to allow browsers to render Grafana in a <frame>, <iframe>, <embed> or <object>. default is false.
allow_embedding = true
[auth.anonymous]
# enable anonymous access
enabled = true
# specify organization name that should be used for unauthenticated users
org_name = Main Org.
# specify role for unauthenticated users
org_role = Viewer
# mask the Grafana version number for unauthenticated users
hide_version = false