When you say that you've "tried to log in to my kindle" what exactly do you mean?
When you set up a new kindle you have to login to your amazon account so that it has access to your online library. When you connect it to your wi-fi, you need to make sure when it scans for any nearby wi-fi signals that you are choosing the correct one that matches your router name. If it's not working you could try restarting your router and verify that you are definitely using the correct password for that router.
Other than that, it's difficult to offer any advice.
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