This is one of the most common issues while installing the SCSM portal and there could be multiple reasons why the SCSM portal may not show up the service requests.
Here is a collation of all the fixes you should try to come out of trouble:
Start with the 5 basic checks suggested by Travis Wright MSFT
1) The Request Offering Published property must be ‘Published’
2) The Request Offering must be included in a Service Offering
3) The Service Offering that includes the Request Offering must have the Published property equal to ‘Published’
4) The Service Offering must be included in a Category (list). The Category list can be edited in the Lists view. It’s called ‘Service Offering Category’.
5) The Service Offering Language must match the language of the browser you are using to connect with. A common mistake is to choose ‘English’ as the language when you are connecting with a ‘English (United States)’ browser.
6) If this does not fix the issue, then make sure that appropriate permission is set in SCSM for users to view the self-service portal. Refer to the blog by Duncan Lindquist.
If still this does not fix the issue, then there may be an issue with the configuration of the portal. Check the following solution proposed by .
Snapshot of the solution from the blog:
1. The webpart and the webservices cant be installed on the same server.
2. When installing the Webpart you must use a FQDN for the webservice including the port
Example: https://scsm01.contoso.com dont work as webservice url but https://scsm01.contoso.com:443 does work
3. When you install it like this you also need goto the server where the webservice is installed and edit the web.config file in the contenthost application with the fqdn.
I used the default location so my web.config file is placed at C:\inetpub\wwwroot\System Center Service Manager Portal\ContentHost\Web.config
<add key="ContentHostAbsoluteUri" value="https://SCSM01:443/ContentHost" />
<add key="ContentHostAbsoluteUri" value="https://SCSM01.contoso.com:443/ContentHost" />
7) Do an IISReset after implementing the solution suggested above and try to access the web portal again.
8) If you are still having the issue, then the issue may be with the certificate. There is a strong possibility that the certificate selected while installing the SCSMWebContentServer and Service Manager Portal was faulty. Check the following blog from Stefan Koell.
9) The blog only suggests fixing the certificate for Service Manager Portal, but you should perform the same steps for SCSMWebContentServer as well.
10) Do another IISRESET and try to access the portal.
All credits to the authors of the blogs. Also, if your issue is still not resolved, then leave a comment so that I can try to repro your issue.