- You can refer the MS articles for instructions on setting up the failover cluster instance https://learn.microsoft.com/en-us/mem/configmgr/core/servers/deploy/configure/use-a-sql-server-cluster-for-the-site-database and SQL server HA https://learn.microsoft.com/en-us/mem/configmgr/core/servers/deploy/configure/sql-server-alwayson-for-a-highly-available-site-database
- For providing HA, you should not keep any client facing roles, storage or anything on the active/passive sites, if you do so, it is not HA because if the server goes down, you lost everything and you need to rebuild from backup or scratch. More information can read from https://learn.microsoft.com/en-us/mem/configmgr/core/servers/deploy/configure/high-availability-options#bkmk_snh
Thanks,
Eswar