You can match and manufacturers rod, with any reel, and any line. In fact the only setup I have that are matching is a dirt cheap rig I keep in my car(don't care if it gets destroyed) that I bought for like $70 including rod, reel, line. You should match your rod to your line weight. RE: 5 wt. line on a 5 wt. rod. sometimes people will use a heavier line such as a 6 wt. line on a 5 wt. reel, but in general stick with the rod maker's recommendation. As to the reel, this has a lot more leeway. but try to get a reel that matches the weight of your setup... not necessarily the line wt. When you hold the rod with the loaded up reel with backing and line it should be somewhat balanced. It doesn't need to be perfect, you should just avoid a setup that has a heavy reel pulling the rod tip up to the sky, or so light , that the tip plunges down. Both are awkward and hard to cast.. but it can be done, (I have some setups that I have to big a reel for)
The main thing is to get the right weight line for your rod, the reason this is critical , is that the line puts the tension on your rod,(like a bow and arrow) if it's too light it won't bend (load) enough, so it'll be hard to cast. If it's too heavy it loads quickly, but the road won't be powerful enough to cast all that weight , so you won't be able to cast as far, or present the fly as delicately.
if you're buying from a shop,(I highly recommend that) they can help . they will have demo rod, reels etc... that you can cast on a nearby lawn, unless the shop is in a city center. I can't suggest this strongly enough. I may cast a rod and think it's awesome, you might think it's ok, another person might think it's awful. We're all different, so hands on always helps. if you're on a limited budget, tell them. most shops have everything from lower cost items to overpriced rods that only a professional will get the most from.
If you post the general are you're located in , I'm sure someone here can recommend a nearby shop that'll help you out
I hope this helps,
let me know if I can help with anything else
The reel must match the size and weight of the rod. Fishing reels differ in the type of construction, the principle of operation, the tackle used, the type of fishing, the method of application, the material of manufacture and performance characteristics.
In addition to the weight, the coil should also be in harmony with the rod in terms of power. For example, let's use the classification of Shimano coils (Japan). Coils of 500/1000 size are suitable for ultra light class spinning rods with a test up to 7g, 1500/2000 sizes are for light and medium–light rods with a test up to 15-20 g, 2500 size is universal and suitable for spinning rods with a test up to 25-30 g, coils of over 3000 size are usually installed on powerful long rods for catching large a predator. Of course, this classification is not strictly mandatory, often when mechanically balancing a tackle, it is better to install a lighter or more powerful coil, depending on the length and weight of the rod.
It depends sometimes. For fly fishing IDEALLY your Rod, Reel and Line are the same WT. But when it comes to balancing the rod and reel, some people get super specific. When it comes to the Spey game, I know for a fact that a 4" Hardy perfect will fit my Redington Claymore 8wt 12'6, but not my 9/10wt 13'9 Hardy Demon. Find a reel that will balance the rod in your hand so it isn't tip heavy, or handle heavy. Then get the corresponding weighted line for your rod and you should be off to the races. What dizhalex said about the spinning reels, is different from fly gear.
Another factor is the rod itself. For example, on my 10wt Sage Salt HD, I put a 12wt line on there, because the rod is so stiff it can handle a heavier line. Some people like to go one line weight heavier to help with casting.