Route using Interface

If we got dhcp from ISP and ‘add default route’ to yes, then how i can make static toute to this interface?

Example i have 2 ISP with dhcp, then in the ip route i got 2 default route. Now i want to make specific traffic to 8.8.8.8 to use ISP2, how i can make this static route?

If i put the ip gateway as nexthop then there will be issue when the ip is changed.

See this recent thread [Solved] Dual WAN set-up, just need final piece of guidance - #8 by Amm0.