The first 5 videos on this page give details of the parts of the instrument, how to hold it and basic techniques:

Parts of the Trumpet

How to hold the Trumpet

The Buzz...

Valve numbers

Tonguing

The next videos, 6, 7 and 8 show how to play the notes C, D and E

The note C played twice for four beats each

The note D

Video 9 above has 2 minims and a semibreve, you will need to play these 2 bars for your silver certificate.