Why does my Windows 10 PC show my default gateway's address instead of the DNS Server IP adresses I've set?

When I go to cmd and type ipconfig /all I can see that the DNS Servers' IP addresses are simply the address of my default gateway (router). Why? When I go to my router settings it does not matter if I set to get dynamically from ISP or set 8.8.8.8, 8.8.4.4 for example, my PC still tells me that my DNS Servers' IP addresses are the IP address of my router. Can anybody explain to me why is this happening and how to fix that? Thank you.

Here's some settings of my router:

Your router uses the DNS servers you configure it to use. It in turn assigns itself as the DNS server for it's DHCP clients. That's a pretty standard configuration. The DHCP clients send DNS queries to the router, which in turn sends those queries to it's configured DNS servers.

There may be options to configure what DNS servers are assigned to DHCP clients in the DHCP Server configuration of the router. Take a look at the DHCP server options of the router and see.

When I go to cmd and type ipconfig /all I can see that the DNS Servers' IP addresses are simply the address of my default gateway (router). Why?

Because that's the way it's been set up by the DHCP server - likely the same device even.

When I go to my router settings it does not matter if I set to get dynamically from ISP or set 8.8.8.8, 8.8.4.

On your router you configure your router's DNS server. To change your client's DNS server, change the DHCP server's scope options.

On many consumer-grade all-in-one routers you can't change the DHCP options but I don't think these things are on-topic here.