Re: advice for beginner
Mochancon... Rods are designed to bend in response to the weight of the fly line. So an 8wt fly rod is very stiff compared to say a 4wt fly rod. The heavier the line the heavier fly that you can cast and the easier to cast into the wind. On the other extreme, an ultra light 3wt rod allows a more gentle presentation.
The second part of the equation after the cast and presentation is the playing of the fish. The rod stiffness should be matched to the weight of the fish and the strength of the leader. If the rod stiffness is too soft for the fight of the fish, you will exhaust the fish before landing it and decrease the chance of the fish surviving if you release the fish. If the rod is too stiff for the fish, the fish can easily break off the tippet when it "runs" or jumps or you end up using such strong leader that _if_ you catch a fish you end up just hauling the fish straight in which I do find very sporting or particularly enjoyable.
One could fish for steelhead trout or salmon both with an 8wt rod.