Flight plan waypoints help a320

Hi

Im following some good tutorials on how to enter a flight plan into the mcdu on the a320neo

Im trying a short flight first but some of the waypoints are confusing me on where I should enter them.

Below is the flight plan, the part that’s got me stumped is T420 and TNT. I think T420 is an airway but when I enter that it doesn’t seem to insert and then TNT I enter that into the waypoint and I get some list come up which Im unsure about.

OFP ROUTE:
-EGKK/26L F240 LAM6M LAM N57 WELIN T420 TNT DAYNE2A EGCC/23L
-DIST 205-

I get its complicated, lol, but would love to try manually entering a plan.

Thanks

Actually not to worry, i’m using old data on SimBrief as don’t have the sub, so that’s likely why some waypoints are incorrect.

Just an update I realise now that the world map has all the waypoints, I did not realise there was a filter to see them and search for them in the search bar. So I now create my plan in the world map as close as I can to any real world flight plan.

There is one area Im not quite sure on though, and that is the destination approach, I realise I can select ILS for pin accurate guidance to landing.

I’m unsure what the purpose of Approach (Automatic) is ?

I have a flight plan set up with a destination arrival, all exact to a real flight plan I found on sky vector, but what does approach (automatic) do?

Thanks