Grammatically these two words are called determiners. It means that they determine what the noun refers to. We use them before a noun in a sentence.
All and every have a very close meaning, but we use them in a different way. ‘All’ determines the whole group, while ‘every’ determines each part or member of the group.
To sum up: ‘all’ focuses on the whole group, ‘every’ focuses on individual part.
All residents should cancel their meetings during the lockdown.
Every resident should cancel their meeting during the lockdown. (We refer to men and women both, that is why we use the pronoun ‘their')
How do we use ‘all’ and ‘every’ with a noun ‘day’?
When we want to show that something goes on during the whole day/week/month/year, we use ‘all’.
When we need to focus on each certain day/week/month/year we use ‘every’.
My family spent all month inside the house during lockdown.
My family spent every day inside the house during a two-month-long lockdown.
I was playing the piano all day long.
I was playing the piano every day during this month.