The sequence of personal pronouns in sentences
First of all，thank you for your help😊.
When more than one personal pronouns appear in one sentence，the sequence of singular personal pronoun is 2-3-1，viz. you, he/she, I. And that of plural personal pronoun is 1-2-3.（Please correct me if I‘m wrong）
But what if there are singular and plural personal pronouns in one sentence at the same time？How do I arrange the order？

Question

The sequence of personal pronouns in sentences
First of all，thank you for your help😊. 
When more than one personal pronouns appear in one sentence，the sequence of singular personal pronoun is 2-3-1，viz. you, he/she, I. And that of plural personal pronoun is 1-2-3.（Please correct me if I‘m wrong）
But what if there are singular and plural personal pronouns in one sentence at the same time？How do I arrange the order？

Answer

As Chris said, the order is not determined by which person ( I/You/He ) but by the meaning in the sentence.  So, for example you could have
I gave it to him / I gave him it.    or
He gave it to me / He gave me it.

So . . . the subject of the sentence is first  (It gets more complicated in the passive voice, but let's skip that for now).
Then follows either the direct or indirect object depending on which form you are using.  To be precise, direct object followed by indirect object prepositional phrase (to me, to him).  Or indirect object if it is just the word, not a phrase.
I'm sorry... it is quite complicated.  Repetition of the type of sentence may help it become more natural to your ear.

Answer

Perhaps you are referring to direct and indirect objects?

I gave a present to my mother.
I - subject
gave - verb
a present - direct object
to my mother - indirect object

I gave a present to my mother.  [subject-verb-direct object-indirect object]
I gave my mother a present.  [subject-verb-indirect object-direct object]

I gave it to her.  [subject-verb-direct object pronoun-indirect object pronoun]
I gave her it.  [subject-verb-indirect object pronoun-direct object pronoun]