If you got Studify from the Roblox Toolbox, you can simply open the toolbox in Roblox Studio and head to the assets that you own. Once you have located Studify in the toolbox drag it into the Replicated storage inside the explorer.
If you have downloaded your studify.lua file direcly from ICrann or via GitHub you will need to find the file inside the file explorer. It will most likely be in your downloads folder. Drag in the studify.lua file into the Replicated Storage in Roblox Studio.
To use Studify place these two lines of code into any script.
local Studify = require(game:GetService("ReplicatedStorage"):WaitForChild("Studify"))
Once you have placed this code into any script you should have Studify available to use in that script.