add setup guide

docs/content/guides/setup.md

@@ -2,4 +2,23 @@
 title: Setup
 ---
 
-TODO
+## User Setup
+
+- **Username**: The username of the user.
+- **Password**: The password of the user.
+- **Confirm Password**: The password of the user.
+
+## Existing Setup
+
+If you have the config from the previous version, you can import it by clicking "Yes". This currently expects a config from v14.
+
+If this is the first time you are using this, you can click "No" to create a new config.
+
+### No - Host Setup
+
+- **Host**: The host of the server. The clients will connect to this address. This can be a domain name or an IP address. Make sure to wrap it in brackets if it is an IPv6 address. For example: `[::1]` or `[2001:db8::1]`.
+- **Port**: The port of the server. The clients will connect to this port. The server will listen on this port.
+
+### Yes - Migration
+
+Select the `wg0.json` file from the previous version. Read [Migrate from v14 to v15](../advanced/migrate/from-14-to-15.md) for more information.