Cluster

MS SQL supports clustering.

First of all it supports Failover Cluster Instances. That is applicable to single SQL server instance across multiple Windows Server Failover Clustering ( WSFC ) nodes. In case if one of the nodes crashes, SQL server automatically passes execution to another one.

Second option is Always On Availability Groups. In this case, each availability group consists of primary replica and one or more secondary replicas. In case of crash, secondary replica becomes primary one. 

If to compare WSFC vs Always on, then Always on doesn't require shared storage.

Big time yes. You can get the HA of SQL Instances using SQL FCI or Database specific using SQL AOAG. Later also helps your distribute RO & RW workloads.  

Bayas1200 , sure, beside SSRS all SQL Server services are cluster-aware; I have 3 clusters running.

See Windows Server Failover Cluster with SQL Server - SQL Server Always On | Microsoft Learn