will be rooting my kids mothers phone tomarrow and i have some questions!!? topic

aight so my kids mother is getting this phone tomarrow off someone and she wants me to root it for her so she can get free hot spot.. im guessing the phone will be on the newest base/firmware.. i kno alot of root methods dont still work so wanted to kno how i will go about rooting this badboy.. root plus custom recovery.. so i can flash a custom rom ect... also are there any good roms that have hot spot working?? sorry for all the question guys! thanks! i have rooted many samsung phones in the past.. the s3 s4.. but never the s2