How to find the exact variable in the string?

Ex:

local noob = workspace.Noob

local word = "lul_"

word = "lul_noob"

a code that checks if "word" has "lul_" and if so, it checks if the string after the underscore matches the object or object name then it does something to the object or thing after the underscore

i have no clue how to do it, i attempted it but i failed miserably