So I made some progress.
Went to system, set the default gateway to 50.x.x.229 and set the name servers as 75.75.75.75 and 75.75.76.76
Went to routing, saw that it appeared there as 0.0.0.0/0 next hop 50.x.x.229
Then I went back to dashboard, found eth7 in the list, and clicked edit. I added the 50.x.x.230/30
I also edited eth0 to have 107.x.x.1/27. Saved the changes.
I then plugged my laptop to eth0, assigned myself a public IP 107.x.x.3/27 with gateway 107.x.x.1 with the same DNS servers as above, and after a minute it worked! However, DNS resolution was painfully slow and pulling up web pages took a while, sometimes having to hit refresh a few times.
When I looked at the Edgeswitch config, it seems the gateway was set to 107.x.x.0 instead of 107.x.x.1 - however, when I input this into the edgerouter it says it's a bad IPv4 network.
Any ideas if I set it up right? Also, any reason as to why DNS doesn't resolve always? When I put everything back on the switch, everything goes quick and smoothly.