>>393906>entry-level hardtail>downhilluhhh....
Well. You should return it and save up for a downhill bike.
If you're deadset on wasting money trying to turn this bike into something it absolutely is not, here is your shopping list:
Tubeless downhill rims: 30mm wide at the absolute minimum
Wider, heavier downhill-oriented tires
Direct-mount stem
Dirt-jumper fork
Dropper seatpost
Bash guard to replace your big chainring
Chain guide/tensioner
Clutched derailleur
Clipless pedals + shoes
180mm+ rotors
At the absolute minimum you need a real fork, a wheelset, tires, pedals, a short (50mm or less) stem, and either a chain guide or a clutched derailleur.