If your domain is registered with Strato, you can access your DNS Zone from your Domains → DNS Editor tab:
You can find detailed tutorials on creating, editing, and deleting DNS records at Strato here: How do I use the STRATO DNS editor?
Hostinger default DNS records:
If you face any difficulties while managing DNS Zone at your domain provider, it’s best to contact Strato directly. Alternatively, you can transfer your domain to Hostinger so your hosting and domain will be managed from one place 😊