I need help, with connecting the wifi to the tv so I can use the mobile app! I lost the remote for the TV and now I switched internet and need to connect it to the internet... I only have the mobile app
Unless you can configure your Wi-Fi settings to match the last network the TV was connected to (same SSID/network name and password), you need a physical remote. There's no way to use the app until the TV is connected to the network. If the TV was never connected to a network or you factory reset it, you must have a physical remote. You may be able to get a cheap universal remote or you may have one lying around from a cable box or some other device that can be programmed to work with the TV.
Roku remotes are sold in many stores like Walmart and Target, etc. for about $20; I had to buy one once when I took my Streaming Stick+ with me on vacation, got to the VRBO house and discovered I'd left the remote at home. Chatted with a Roku support rep who suggested where to go buy one, so I did and now have a spare remote.