All & Both

Before “the” “these” “those” “his” “our” (both can be acceptable; “all” is preferable in formal style)
✅ All the things have been cleared up.
✅ All of the things have been cleared up. (ok, but not necessary, not a must)

Before a “general” noun (factual statements)
✅ All reactions require attention. (a fact)
❌ All of reactions require attention.

Before a personal pronoun (them, us, which)
✅  All of them have been completed.
❌  All them have been completed.
❌  All they have been completed.

✅  All we believe.
(This sentence is correct, but English speakers would interpret this as "everything we believe" and not "everybody believes.")

✅  All they are thinking.
(This sentence is correct, but English speakers would interpret this as "everything they are thinking" and not "they all are thinking.")

Before pronouns
✅  Both of us are ready.
❌  Both us are ready.

After pronouns
✅  They both are ready.
❌ They both of are ready.

To intro two options
✅  Both Option A and Option B are feasible, however, we’re leaning more towards the former one.
❌  Both of Option A and Option B are feasible, however, we’re leaning more towards the former one.

With plural nouns
✅  Both reactions worked well.
✅  Both of the reactions worked well.
❌  Both the reactions worked well.