Gaikokujin

Hello guys! I decided to replace my ISP router with my own router (ASUS RT-AX53U) in order to have better and more advanced control over my home network, especially since I have several IoT devices. If anyone has hands-on experience with a similar setup, please let me know what I should consider before replacing the ISP router and whether there is a safe step-by-step guide for doing it properly without breaking the existing network.