Look on line for a blacksmithing association in your country, or a nearby country, for starters. Most schools assume some level of competence for prospective students, so I would contact the various schools to determine what prerequisites, or what level of skill is necessary to complete their blacksmithing programs, prior to enrolling. A small forge can be made, with not too much trouble, and almost any block of steel can be used as an anvil, so setting up a crude, but usable shop is not all that difficult. There are a few videos on Youtube illustrating how this can be done, and almost any general purpose hammer can be used for blacksmithing.
Bealer's book of blacksmithing is a must. Forging buttplates, triggerguards, and other assorted parts is not difficult, for an relatively new smith, as long as one understands how metal moves. The important first lesson is learning how metal moves, under the hammer. Buy a couple of blocks of modeling clay, a toy hammer, or use your finger to press on the block to learn how metal moves, by "forging" various items, using your fingertip to move the clay into the desired shape. I suggest doing that after reading Bealer. There are also quite a lot of good blacksmithing videos on YouTube, to give you some idea of what is necessary to get started, and some excellent videos on virtually every aspect of blacksmithing.
There are a number of good building videos on Rumble, posted by Bill Raby. Search for Maryland Longrifle build, Four bore rifle build, Tennessee Rifle Build, or fusil-de-Chasse build in addition to buying several building DVDs by Herschel House, Mike Miller, and James Turpin, to name a few. IMHO, the best book on building longrifles is "Recreating the American Longrifle, by Buchele, Shumway, and Alexander. The "Gunsmith of Grenville County" is also good, as are some other books.
As mentioned earlier, learn to make small parts, by hand, using hacksaw, file, and other hand tools.
You have begun what can become a long, arduous journey, that will take determination, discipline, time, sweat, and money to learn. Some of the skills can be self taught, some cannot. I wish you good luck in this, often, consuming hobby.
J.D.