Windows 10 | WiFi connected but No Internet Access | DNS server isn't responding
If your Windows 10 is losing WiFi signal strength and says "No Internet Connection" while other devices are connected just fine, chances are, DHCP Server didn't hand your Windows Device a valid IP address. The solution resides in the following steps:

Go to Settings > Network & Internet > Wi-Fi
Click on your network's SSID (the name of your Wi-Fi network e.g. Home Wifi)
Set the Network Profile to Private
Scroll down to IP Settings and click Edit
Change from Automatic (DHCP) to Manual
Toggle IPv4.
Run as Administrator Command Prompt
Type the following command ipconfig /all and hit enter
Scroll down to DHCP Server. Copy that number by highlighting it with your mouse and pressing Enter.
Back in the Settings window we opened in step 01, paste the number you copied from Command Prompt in the IP Address field. The number should look something like this after you paste it: 192.168.1.1
Delete the last digit, in my example in step 10, it's the red 1.
Type any number of your choosing between 5-30
In the Subnet Prefix Length field, paste this exact number: 255.255.255.0
In the Gateway field, paste the exact number you copied in step 10. In my example, it's 192.168.1.1
In Preferred DNS field, paste this number: 8.8.8.8
In Alternate DNS field, paste this number: 8.8.4.4
Click Save.
In case the internet didn't work, repeat from step 12 to step 17. This time try a higher number than the one you chose earlier in Step 12.

This should solve your problem in case you have already tried the below methods and they didn't work. If you haven't, and the problem persists, try these methods until one of them works.

METHOD #1

Reset Network Adapter and DNS using Command Prompt

Run as Administrator Command Prompt
Type the following commands, pressing enter after finishing each one:
netsh winsock reset

ipconfig /release

netsh int ip reset

ipconfig /flushdns

ipconfig /renew

Exit Command Prompt

Restart your PC.

If the problem persists, try Method #2

METHOD #2

Reset Network Adapter using Device Manager

Click Windows button + X
Select Device Manager
Open Network Adapters
Right-click on your network adapter, click Uninstall device. In the window that pops up UNCHECK Delete the driver software for this device.
Click Uninstall button
Restart Your PC
It should reinstall your adapter automatically. If it didn't, follow Step 01 and 02. Then, Click Action > Scan for hardware changes from the top menu lists.

If the problem persists, try Method #3

METHOD #3

Update Your Network Adapter Driver

(This is for more advanced users, proceed at your own risk)

Click Windows button + X
Select Device Manager
Open Network Adapters
Notice the make and model, including numbers and letters of your network adapter. Recommended Action: Write them down on a paper.
Use Bing or Google by typing what you copied from Step 04 in the search field.
The top results should be your Network Adapter manufacturer. If your network adapter is Qualcomm Atheros, make sure you go to Qualcomm.com and not any other site.
Find the Downloads page, usually, manufacturers list it within the Support page.
Find your network adapter's model (the numbers and/or letters that follow the manufacturer's name, example: Atheros 954xxx)
Download the latest driver, if available.
Do NOT download any driver that does not has the exact model number and/or letters. If one number is different (e.g. 955xxx instead of 954xxx) do NOT download it, installing the wrong driver will damage your hardware irreversibly. If you're not sure, I recommend hiring an expert.

Assuming you found your correct driver, and now that the download is finished, you need to update your network adapter's driver. Follow the steps below.

Click Windows button + X
Select Device Manager
Open Network Adapters
Right-click on your network adapter > Update Driver
A window will pop up. Choose Browse my computer for driver. On the next window, click the Browse... button.
Locate the driver you downloaded from the website.
Press select.
Restart your PC

Sorry, link HERE ...