If your domain is pointed to the Hostman nameservers, you can manage the domain's DNS records in the Hostman dashboard.
To open the DNS editor:
Here you can manage the DNS records of your domain.

To edit an existing record, click on it, make your changes, and save.

To add a new record, click on Add DNS record, select the record type, add the values, and save.
To delete a DNS record, click on three dots and click Delete. Confirm deleting the record.
For example, to update the A record of your domain:

Usually, updating the A record will take up to 3 hours; in rare cases, in can be up to 24 hours.