You won’t be able to connect your Toshiba external HD unless it can generate its own WiFi hotspot.
There are two kinds of external storage that can be used with an iPad:
1) Flash drive using the Apple USB Camera Adapter
2) Wireless hard drive, such as certain models by Western Digital, SanDisk, Seagate, to name a few. The data transfer is facilitated by an app.
External hard drives that work only by USB connection cannot be used with iPad.
Here are few examples of WiFi external hard drives:
Seagate Wireless Plus 1TB Portable Hard Drive with Built-in WiFi (STCK1000100)
https://www.amazon.com/dp/B00AQRUW4Q/ref=cm_sw_r_sms_c_api_yCXhAbJ4SDNBM
WD 2TB My Passport Wireless Pro Portable External Hard Drive - WIFI USB 3.0 - WDBP2P...
https://www.amazon.com/dp/B01F5LVTO4/ref=cm_sw_r_sms_c_api_QEXhAbR2BXB7J
RAVPower FileHub Plus, Wireless Travel Router, SD Card Reader USB Portable Hard Driv...
https://www.amazon.com/dp/B016ZWS9ZE/ref=cm_sw_r_sms_c_api_ZzXhAb8611V0J