'Shall' does not change its form.
I, you, he, she, it, we, they shall.
'Shall' is also shortened to...'ll.
I'll, you'll, he'll, she'll, we'll, they'll - and even (although it's not good English) it'll
The negative of 'shall' is 'shall not' - often shortened to shan't
I, you, he, she, it, we, they
shall not / shan't
In British English 'Shall' is often used instead of will in the first person (I/we).
I / We will = I / We shall
I shall be at work on time. = I will be at work on time.
We shall win the competition. = We will win the competition.
They shall not pass! = They shan't pass!
'Shall' is also often used in the first person (I/we) in questions when asking for permission, making suggestions, making an offer or asking for advice.