To install unpack the 7z you downloaded, then copy the mod file (pak) to where your game is installed and your ~mods folder is:
"[Path-To-Steam]\steamapps\common\Hogwarts Legacy\Phoenix\Content\Paks\~mods"

What's in the mod.

V1

Longer spell distance cast
Stronger spell forces
No spell time
Extra spell damage
All spells unlocked
More gear spaces
Free gear/broom upgrade 
Quick make potions
Quick upgrades
More health


What's in V2 of mod

Longer spell distance cast
Stronger spell forces
No spell time
Extra spell damage
All spells unlocked
More gear spaces
Free gear/broom upgrade 
Quick make potions
Quick upgrades
More health
*Any spell break/cancel shield
*Student in common areas at night
*All travel spots unlocked
*100% Shiny beast

V3

Unlocked all Conjurable Items, Added 100 slots to all conjured items
999 plants and potions
Extra x2  XP Bonus 
Instance Hopping pot, Materials Refiner Mistcomposter and Choppingstation Cooldown
Sell items for 99999
Train spawn 7 times a day 7 weeks
6x Enemies spawn
Longer spell distance cast
Stronger spell forces
No spell time
Extra spell damage
All spells unlocked
More gear spaces
Free gear/broom upgrade 
Quick make potions
Quick Grow Plant
Quick upgrades
More health
any spell break/cancel shield
Student in common areas at night
All travle spots unlocked
only 2 set typers of gear
100% Shiney beast
*Might Lag when you open your first few chest.*