Level is the level of the attacking Pokémon
Power is the base power, e.g. Tackle has 40 Base Power
Atk is your Pokémon's Attack or Special Attack stat (depending on what you're using)
Def is your opponents Defense or Special Defense stat (depending on the attacking move)
Targets is 0.75 or reduces by 25% is the move is attacking multiple targets e.g. surf in a double battle
random is a multiplication from a random integer between 85 and 100, inclusive, then divided by 100. Decimals are rounded down to the nearest integer
STAB is the same type attack bonus which is 1.5x if the move you used is the same type as you Pokémon
Weather is 1.5 for water type moves in rain and 0.5 for fire type moves, and in harsh sunlight, 1.5 for fire type moves and 0.5 for water type moves.
Critical is for critical hits which is a 1.5 bonus if you're lucky
Burn is the reduction of damage of physical moves (Atk)
The rest is pretty specific
GlaiveRush details the effects of the move as a number. It would be 2 if the opponent used it previously
PB doesn't apply to Gen 9. It's the bonus from Parental Bond
Zmove is if the opponent if using protect or similar moves and you use a Z-move. It would be 0.25
TeraShield is applied in Tera Raid Battles when the Raid boss's shield is active, and is 0.2 if the player's Pokémon is not Terastallized, 0.35 if it is but the used move is not of its Tera Type, and 0.75 if it is and the used move is of its Tera Type. The result is subject to standard rounding, rounding up at 0.5.
other is other factors from Abilities or moves
This system has been used since Gen 5
I basically just copied this from Bulbapedia but I hope I helped!
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