Switch statements in access in SQL Server

Hi Im trying to transorm some access database, reports queries etc into SQL Server.

I'm having issues with some of the queries where they are group by and counts using switch statements in access

see below.....how would i mimic this in sql server?

SELECT tblStaff.Full_Name, tblCompany.Managed_Account_Agent, tblStaff.Manager, tblStaff.Email, Count(tblCompany.Managed_Account_Agent) AS [TOTAL MAs], Count(Switch([REMOVE_FROM_LEADCHECKING_PLATFORM] Is Null,[Managed_Account_Agent])) AS [TOTAL F2C MAs], Count(Switch([REMOVE_FROM_LEADCHECKING_PLATFORM] Is Null And [Actual_Number_Of_Employees]>1 And [Mobile_Provider]>"" And [PMOBHAND]>0 And [EXP_Date] Is Not Null,1)) AS [Mobile_Profile F2C], ([Mobile_Profile F2C]/[TOTAL F2C MAs]) AS [Mobile_Profile F2C %]
FROM tblCompany INNER JOIN tblStaff ON tblCompany.Managed_Account_Agent = tblStaff.SystemName
GROUP BY tblStaff.Full_Name, tblCompany.Managed_Account_Agent, tblStaff.Manager, tblStaff.Email
HAVING (((tblStaff.Manager)<>"leaver"));