Each airline has their procedures and policies.
Generally, takeoffs are flown packs OFF.
Flaps 10 or 20...
If you really want a pack, use the APU bleed with nš 2 pack.
Provided that your APU is not placarded "GND USE ONLY".
For landing, some airlines use flaps 25, some 30.
Auto brakes to minimum, idle reverse works fine.
xxx
I am a "Classic" 747 guy - but above applies to 744 as well.
Happy contrails