How to Install and Enable the Clear Lava and Water Resource Pack
Placing the Pack in Your Resource Packs Folder
A resource pack is not a mod loader file, so you do not drop it into your mods folder. Instead, you place the pack file into the resourcepacks folder inside your Minecraft game directory. On most launchers you can reach this folder from the Options menu: open Options, then Resource Packs, then click Open Pack Folder. Copy the pack file into the window that opens.
Activating It In-Game
Return to the game and open Options > Resource Packs again. Your pack should now appear in the left-hand column under Available. Click its icon so it moves to the Selected column on the right. Make sure it sits above any other pack that also changes water or lava textures, since packs lower in the list are overridden by packs above them. Click Done to apply.
Confirming It Works
Submerge yourself in a body of water and look around. If the pack is active, the blue tinted overlay that normally covers your screen should be gone, and you should see the underwater terrain clearly. Repeat the check in lava. If nothing changed, verify the pack is actually in the Selected column and that no higher pack is overriding it.