WebDAV

First, the WebDAV server on the NAS must be enabled.

Synology : How to access files on Synology NAS with WebDAV.
QNAP : Accessing your QNAP NAS remotely with WebDAV.
ASUSTOR : Connect to your NAS via WebDAV using a variety of different devices.

Configuring DDNS Service Settings

Synology :
Go to Synology DiskStation Manager(DSM) > Control Panel > External Access > DDNS > ADD, register the hostname, click Test Connection to check the normal status, and then click the OK button. Click here to learn more about Synology DDNS service.
QNAP :
Go to QNAP Turbo NAS Software(QTS) > Control Panel > Network & File Services > Network & Virtual Switch > Access Services > DDNS > Add, configuring DDNS Service settings and click Apply button. Click here learn more about Configuring DDNS Service Settings.
ASUSTOR :
Go to ASUSTOR NAS Admin Center > Manual Conncet > DDNS, enable DDNS service, configuring DDNS Service settings and click Apply button. Click here to learn more about ASUSTOR DDNS service.

New Drive

1.Under Storage, select the WebDAV in the NAS tab.

2.Select the required options.

3.Select the protocol (http/https) with the checkbox to the right of the address label, and enter server address, port number, username, password.

Options

Enter the path to the server to use as the top-level folder.
If you are not using an account, click the Anonymous checkbox.

4.Click the TLS/SSL drop-down list to select the TLS/SSL version. (Supported when https is selected)

TLS/SSL Versions

Select the RaiDrive TLS/SSL version based on TLS version compatibility setting on your NAS.

Synology : Click to learn about versions supported by each compatibility level.
QNAP : Click to learn about enable secure connection (HTTPS).
ASUSTOR : Click to learn about TLS Version.

5.Click the Timeout drop-down list to select the Timeout second, and then click the Connect button.

6.The connected drive is created in the Network locations of File Explorer.

Drive Connect/Disconnect

1.Clicking the Disconnect button() removes the WebDAV you've connected from the file browser.

2.When you click the Connect button(), WebDAV will be created in the Network locations of the File Explorer.

Drive Edit

1.If the drive is connected, click the Disconnect button().

Attention

Editing is not possible while the drive is connected.

2.Click the Edit button().

3.Change any options that require correction, or select advanced options and click the OK or Apply button.

Drive Remove

1.If the drive is connected, click the Disconnect button(), then click the Delete button.()

2.When you click the OK button, the drive is removed from the list of connections.