You can edit the Content of the domain names you own, you can for instance store an IPFS CID or an Arweave hash to use the domain name for a DApp.
Visit https://naming.bonfida.org/#/domain-registration and search for your domain name
Connect the wallet with which you own the domain, two more buttons will appear: Transfer and Edit
To edit the content stored in the account of the domain name click on Edit and enter the content you want to write in the domain name account, then click Edit and confirm the transaction
You can transfer the ownership of the domain name to another SOL address by clicking on Transfer