Some video tutorials are published online:

• The ns-3 Consortium has published some training videos authored by ns-3 maintainers.
• A tutorial on Wi-Fi simulations with ns-3 was presented at the Latin America Networking Conference (LANC) in October, 2022. This updated a similar tutorial on Wi-Fi simulations with ns-3 presented at ACMSE Conference in April 2022.
• A tutorial on 5G New Radio Simulations with ns-3 was presented at ACMSE Conference in April 2021.
• Several community-contributed videos are available on YouTube

Several screencapture videos on installing and using ns-3 and NetAnim are available:

• John Abraham has several NetAnim demonstration videos posted at his ns3share page