Depending on route, either about 3 1/2 hours or 4 1/2 hours. The route through York is the longer one if memory serves.
You can't travel from Edinburgh to Belfast by train because Belfast is in Ireland which is an island. The easiest way is to fly.
About 1 hour and 50 minutes
About 7 hours
St. Andrews does not have a train station. Leuchars is the closest.
4 hours 30 minuites
The train takes about 2 hours 30 minutes.
About 4 hours.
About 4 hours 30 minutes.
About four hours and you will have to change trains at York.
About 3 hours 30 minutes.
About 2 hours 30 minutes.
There are no direct trains between Holyhead and Edinburgh - you will have to change trains at least once. The journey time will be about 6 hours dependent on which train you catch.