You can add component license keys in the SDDC Manager UI or add a solution license key in vSphere Client.

Starting with VMware Cloud Foundation 5.1.1, you can license VMware Cloud Foundation components using a solution license key or individual component license keys.
Note: VMware Cloud Foundation 5.1.1 supports a combination of solution and component license keys. For example, Workload Domain 1 can use component license keys and Workload Domain 2 can use the solution license key.

For more information about the VCF solution license key, see https://knowledge.broadcom.com/external/article?articleNumber=319282.

SDDC Manager does not manage the solution license key. If you are using a solution license key, VMware Cloud Foundation components are deployed in evaluation mode and then you use the vSphere Client to add and assign the solution key. See Managing vSphere Licenses for information about using a solution license key for VMware ESXi and vCenter Server. If you are using a solution license key, you must also add a separate VMware vSAN license key for vSAN clusters. See Configure License Settings for a vSAN Cluster.
Note: After you assign a solution key for vCenter Server, VMware NSX automatically uses that solution license key.

Use the SDDC Manager UI to manage component license keys. If you entered component license keys in the deployment parameter workbook that you used to create the management domain, those component license keys appear in the Licensing screen of the SDDC Manager UI. You can add additional component license keys to support your requirements. You must have adequate license units available before you create a VI workload domain, add a host to a vSphere cluster, or add a vSphere cluster to a workload domain. Add the necessary component license keys before you begin any of these tasks.