There are different plans.
The cheapest "Safety" costs CHF 19.90
See here:
https://www.garmin.com/de-CH...With the Safety Plan you can send unlimited SOS messages to the Garmin team, which in turn alerts the local rescue service. Depending on the weather, however, this can take a good 2-3 days, so always be aware of this.
And rescue insurance is also advisable, as the transport costs can quickly become very high, you can also buy this through Garmin from CHF 50.
It's also worth mentioning that you can pause the plan at any time so that you don't have to use the 30 days for the safety plan in one go, which is very practical.
The 10 messages specified in Safety refer to messages that you want to send to another InReach or to friends via the "Messeger" app from Garmin to friends without InReach.