@Brittany01
If you have already tried restarting your router, you will most likely have to access the router admin settings and verify that it is configured properly for use with your Roku devices.
Agood starting point is here with basic info.... https://community.roku.com/t5/Network-Wireless-Wired-Connections/Wireless-Network-Troubleshooting-He...
If you know how to access your router, verify that both the 2.4ghz and 5ghz radio are still enabled and broadcasting. Under Wireless Settings in your router, try assigning "Wireless Channel" under 2.4ghz to a number between 1 and 11. Under 5ghz, you will need to use "Wireless Channel" number 36-48 or 149-161. (Roku cannot see other wireless channels other than these.) Most routers are configured to "automatically" assign a channel which is often the issue as it selects an incompatible channel.
As a starting point, you can also use a hotspot to complete your setup (if available to you). Otherwise, take the Roku to another location (family/friend) to complete setup. However, until you configure your network to reflect the settings above, will most likely still not connect at your own wifi after successful setup.
Post back with your Roku model nubers and router model number if you need more detailed help or help accessing the router.
Roku Community Streaming Expert
Just another Roku user... I am not a Roku employee.
Insignia RokuTV, Ultra 4660, Premiere+ 3921, Express 4k+ 3941, Streambar 9102
