Getting an object to spawn on a set time

Hi i am a modeller so i cant script and i was wondering how to get health packs to spawn every 5 seconds and then after a 30 seconds period the object spawns every 10 seconds then in another 30 seconds it spawns every 15 seconds thx

Try watching these two videos:

Then combine the knowledge you learn from both of these videos and you will be able to instantiate any object at any given interval.