How to configure the default route for each device

I want to create a default route for each client pointing to a different gateway. This can be done using ip route add. Is there any other way to do this with Netplan? After I configured Netplan for zerotier, the zerotier network card cannot get an IP address.

ztvuwp6scr: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 2800
        inet 10.2.165.242  netmask 255.255.0.0  broadcast 10.2.255.255
        inet6 fe80::44e1:baff:fe28:4376  prefixlen 64  scopeid 0x20<link>
        ether 46:e1:ba:28:43:76  txqueuelen 1000  (Ethernet)
        RX packets 0  bytes 0 (0.0 B)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 11  bytes 866 (866.0 B)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

root@ubuntu:~# netplan set ethernets.ztvuwp6scr.dhcp4=true
root@ubuntu:~# netplan apply
root@ubuntu:~# ifconfig
ens3: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500
        inet 192.168.0.23  netmask 255.255.255.0  broadcast 192.168.0.255
        inet6 fe80::f816:3eff:fe43:9afe  prefixlen 64  scopeid 0x20<link>
        ether fa:16:3e:43:9a:fe  txqueuelen 1000  (Ethernet)
        RX packets 21696  bytes 44422326 (44.4 MB)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 18129  bytes 2516760 (2.5 MB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

lo: flags=73<UP,LOOPBACK,RUNNING>  mtu 65536
        inet 127.0.0.1  netmask 255.0.0.0
        inet6 ::1  prefixlen 128  scopeid 0x10<host>
        loop  txqueuelen 1000  (Local Loopback)
        RX packets 210  bytes 20436 (20.4 KB)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 210  bytes 20436 (20.4 KB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

ztvuwp6scr: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 2800
        inet6 fe80::44e1:baff:fe28:4376  prefixlen 64  scopeid 0x20<link>
        ether 46:e1:ba:28:43:76  txqueuelen 1000  (Ethernet)
        RX packets 0  bytes 0 (0.0 B)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 15  bytes 1448 (1.4 KB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0