earplugs and HG earplugs (high grade earplugs) is a skill that is put onto your armo(u)r and/or weapon, if you have unlocked the decoration in the forge you may craft it, but i believe it's a more later game skill.
However some more things to help
-when you bring potions and mega potions you wanna try to bring honey and blue mushrooms with you, the blue mushrooms and herbs make potions and the honey will give you 10 extra mega potions when you mix them with your regular potions.
-Try to get your hands on adamant and might seeds (eating these will raise your def and att) (in case you had not known). You CAN mix these for pill versions as well (you need immunizers to mix them)*Immunizers take catalyst and dragon toadstool, catalysts take honey and bitterbugs* (Catalysts and might/adamant seeds can make demondrugs and armorskins, you can once again mix these for "mega" versions which need pale extracts, they need to be grinded from Gigginoxes.
-Later on if not where you are, in the shop at the guild you may have unlocked armo(u)r and power charms, buy 2 of each if possible, you can only use one but you can fight deviljho for their talons and you mix those talons with 1 of each charm.
In total you should have a armo(u)r charm and talon and power charm and talon.
-*In case you don't do this* Don't be afraid to run away from the monster whether it's in rage mode or if you need to sharpen, etc. As long as you can kill the monster in time do what's necessary not what is fastest.
-Also Google WILL be your best friend on your journey, you will be using it to research what materials come from where, what are monsters weaknesses.
Although most of the time if you can get your hands on Brachydios weapons they will probably be one of your most used if you end up liking them as they pretty much are good on most monsters.
-The last of my tips to add to this wall of text is, grind Royal Ludroth for "Dash Extracts" mix these with Well-done steaks for "Mega Dash Juice", this will give you infinite stamina for a period of time as well as builds up your stamina bar.
I hope I helped! and sorry for getting carried away on the wall of text