Larian Studios Forums Baldur's Gate III Baldur's Gate III - General some questions about spells

Thanks a lot

So about the warlock multiclass this means:
Lets say I have a lv3 warlock/lv5 sorcerer. (this is character level, below I will use spell level)
I have 2 warlock spell slots of level 2 and I have sorcerer spell slots up to lv3.
This means I could cast any warlock spell and any sorcerer spell of lv1 or 2 as a warlock spell slot and it would always have the effect of a level 2 spell.
I cannot cast a lv3 sorcerer spell using my warlock spell slots.
I can cast any warlock spell and chose if I use a lv1, 2 or 3 sorcerer spell slot, except that I cannot use a lv2 warlock spell with a lv1 sorcerer spell slot.

about
- Can you cast all spells with a slot of a higher level, even if the description does not mention an additional effect at higher levels?
Lets say I have the shield spell (as example for a spell with a description that does not mention higher levels), I have already used all of my lv1 slots but I still have slots of higher level.
If an enemy casts magic missle at me, can I react with shield using a lv2 slot or higher?
Edit: I do not know all spells, but for example stinking cloud has no text about higher levels. If you have a spell that can make an entire group of enemies helpless, its probably useful to cast it with a higher level slot, even if the higher level has no bonus effect, assuming you could do that.