This page explains how to get online via a wireless connection with your Nintendo Switch.
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Nintendo Switch: How to Connect to Wifi Internet Network
Switch] Can I use my Nintendo Switch Pro Controller with a wired connection?, Q&A, Support
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How to Manually Set Up a Wireless Internet Connection, Support
Switch] How can I stop all wireless communications? (Airplane Mode settings), Q&A, Support
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Nintendo Support: How to Connect to the Internet Using a Wireless Network
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