When upgrading across major versions saving a copy of your config to your “desktop” is a good idea. It is a tar file, which you can then extract and look at for reference.
Many times config from vN works just fine with vN+1. However going from ar71xx to ath79 is a major change and the upgrade scripts aren’t perfect. You may find no wireless or Ethernet ports swapped if you take the default and keep your existing config with sysupgrade or LuCI.
Going from vN to vN+2 or later is likely to cause problems with existing config.
Thanks for your help guy's Everything worked out great, Soon I just got one more thing to figure out I installed travelmate and got it working but there is no IPv6 only IPv4