Contact the folks that manage your DNS and ask them to add records for test-systems.co.uk and www.test-systems.co.uk . If DNS is already done, then simply configure the bindings in IIS.
Configuring Http to https redirect on IIS is a Google search away. I've used the following for years and if I recall I just used the GUI interface in IIS.
<?xml version="1.0" encoding="UTF-8"?>
<configuration>
<system.webServer>
<rewrite>
<rules>
<rule name="http to https" enabled="true" patternSyntax="Wildcard" stopProcessing="true">
<match url="*" />
<conditions logicalGrouping="MatchAny">
<add input="{HTTPS}" pattern="off" />
</conditions>
<action type="Redirect" url="https://{HTTP_HOST}{REQUEST_URI}" redirectType="Found" />
</rule>
</rules>
</rewrite>
</system.webServer>
</configuration>
Of course, you firewall must allow port 80 traffic.