Explain 30 year fixed FHA loan please

[Jonathan H.]

Hi guys,

Im a Canadian citizen buying in the US and have been telling my family about the loan I will be getting.

I will be getting a 4plex at ~4.5 for 30 years fixed.

Now, both sides of my family (in Canada) are saying: "We've never heard of that. The longest we've locked in rates were 5-10 years etc).

What, this has me confused. I asked the broker out right: "What can change my rate during these 30 years"

His answer was that nothing can change it. Its secured for 30 years.

Can someone explain this to me? Is the broker correct?
I will have a rate of ~4.5% for 30 years? Without worrying about an increase?

thanks