Root@Pc:/Etc/Wireguard# ip r default via 192.168.1.1 dev enp1s0 proto dhcp metric

100
10.66.0.0/24 dev wg0 proto kernel scope link src 10.66.0.1
169.254.0.0/16 dev enp1s0 scope link metric 1000
192.168.1.0/24 dev enp1s0 proto kernel scope link src 192.168.1.2 metric 100

root@pc:/etc/wireguard# traceroute 192.168.1.1
traceroute to 192.168.1.1 (192.168.1.1), 30 hops max, 60 byte packets
1 router.lan (192.168.1.1) 0.559 ms 0.540 ms 2.178 ms

root@pc:/etc/wireguard# traceroute 192.168.1.14
traceroute to 192.168.1.14 (192.168.1.14), 30 hops max, 60 byte packets
1 192.168.1.14 (192.168.1.14) 33.753 ms 33.703 ms 33.682 ms

root@pc:/etc/wireguard# traceroute 8.8.8.8
traceroute to 8.8.8.8 (8.8.8.8), 30 hops max, 60 byte packets
1 10.66.0.2 (10.66.0.2) 8.267 ms 8.195 ms 8.138 ms
2 router.lan (192.168.1.1) 8.120 ms 8.240 ms 8.223 ms
3 10.25.100.1 (10.25.100.1) 8.376 ms 8.357 ms 8.308 ms
4 10.8.2.14 (10.8.2.14) 10.215 ms 10.240 ms 10.334 ms
5 10.8.2.13 (10.8.2.13) 8.321 ms 8.302 ms 8.444 ms
6 109.110.48.22 (109.110.48.22) 8.640 ms 3.536 ms 3.516 ms
7 109.110.48.21 (109.110.48.21) 10.241 ms 10.325 ms 10.872 ms
8 109.110.48.89 (109.110.48.89) 10.838 ms 11.008 ms 11.054 ms
9 87.226.230.241 (87.226.230.241) 5.616 ms 5.718 ms 5.675 ms
10 213.59.211.151 (213.59.211.151) 125.641 ms 125.799 ms 125.900 ms
11 79.133.79.90 (79.133.79.90) 117.819 ms 117.976 ms 113.825 ms
12 108.170.250.33 (108.170.250.33) 118.757 ms 108.170.250.65 (108.170.250.65) 119.454 ms 108.170.250.97 (108.170.250.97) 118.804 ms
13 209.85.243.39 (209.85.243.39) 119.387 ms 108.170.227.81 (108.170.227.81) 119.563 ms 108.170.232.203 (108.170.232.203) 119.595 ms
14 google-public-dns-a.google.com (8.8.8.8) 113.665 ms 113.476 ms 114.969 ms

root@pc:/etc/wireguard#

почему в 8.8.8.8 пошли через туннель?

По правилам маршрутизации. Ваш К.О.