Does hold person work on monsters that are humanoid, for example, giants, lizardfolk, troll, bugbear etc.? Or would I need to cast hold monster for it to work? Also is hold monster a better version of hold person?
It works on creatures of type "Humanoid". The type is a specifically defined feature of each creature on its stat block. If the examples you gave, Lizardfolk and Bugbears have the type Humanoid so the spell works on them. Giants and Trolls have the type "Giant" so Hold Person is insufficient. The Monster listing on this site is very handy for listing monsters by type for things like this spell.
Note that the word "monster" has no legal meaning in this ruleset. All humanoids are equally humanoid. [REDACTED]
Hold monster targets everything that is a creature, provided it is not immune to being paralyzed, has range of 90 ft
Hold person targets creatures with the "humanoid" type only. You can use DDB to filter on Humanoid to make sure you know which is which. Also you can find it in italic under the name of every creature in their stat block, after their size. For example; Acolyte is a Medium humanoid, thus susceptible, while a Hill Giant is humanoid in shape, it is in fact a Huge giant. Just look at the typing underneath the name to make sure. Also the spell's range is 60 ft, so in some cases you may want to cast Hold monster on a humanoid if he's farther away. Otherwise I think the only difference is what they can target.
Does hold person work on monsters that are humanoid, for example, giants, lizardfolk, troll, bugbear etc.? Or would I need to cast hold monster for it to work? Also is hold monster a better version of hold person?
It works on creatures of type "Humanoid". The type is a specifically defined feature of each creature on its stat block. If the examples you gave, Lizardfolk and Bugbears have the type Humanoid so the spell works on them. Giants and Trolls have the type "Giant" so Hold Person is insufficient. The Monster listing on this site is very handy for listing monsters by type for things like this spell.
Note that the word "monster" has no legal meaning in this ruleset. All humanoids are equally humanoid. [REDACTED]
The differences are basically this:
Hold monster targets everything that is a creature, provided it is not immune to being paralyzed, has range of 90 ft
Hold person targets creatures with the "humanoid" type only. You can use DDB to filter on Humanoid to make sure you know which is which. Also you can find it in italic under the name of every creature in their stat block, after their size. For example; Acolyte is a Medium humanoid, thus susceptible, while a Hill Giant is humanoid in shape, it is in fact a Huge giant. Just look at the typing underneath the name to make sure. Also the spell's range is 60 ft, so in some cases you may want to cast Hold monster on a humanoid if he's farther away. Otherwise I think the only difference is what they can target.
Hope it helps.
Subclass: Dwarven Defender - Dragonborn Paragon
Feats: Artificer Apprentice
Monsters: Sheep - Spellbreaker Warforged Titan
Magic Items: Whipier - Ring of Secret Storage - Collar of the Guardian
Monster template: Skeletal Creature
* Except undead. That bit's an artifact of 3rd edition rules that slipped through.
The Forum Infestation (TM)
Subclass: Dwarven Defender - Dragonborn Paragon
Feats: Artificer Apprentice
Monsters: Sheep - Spellbreaker Warforged Titan
Magic Items: Whipier - Ring of Secret Storage - Collar of the Guardian
Monster template: Skeletal Creature
Thanks guys that really helped