In case, you find the need to change the DNS server for your entire network on your router or set it individually on a PC or other device then have a look on this tutorial.
If your Windows operating system notifies you about weak Wi-Fi signal then it means your connection is not up to the mark. In order to boost the signal for your wireless network (WLAN), try this tutorial.
In case, you are a Raspberry Pi enthusiast then you should configure your Raspberry Pi for remote access. With this tutorial, you can remotely connect to your Pi as well as activate a Wi-Fi add-on dongle.