inserting Cells

What are the $3$ ways you can insert cells?

a$.$ Right click on your mouse and select "insert"

b$.$ Go To "Insert" in the ribbon at the top and select "insert"

c$.$ Right click on your mouse and select "add"

d$.$ Go To "Home" in the ribbon at the top and select "insert"

e$.$ Use quick key shortcuts: ALT $+$ I $+$ E $($PC$),$ Cmnd $+$ Shift $++($Mac$)$

f$.$ Use quick key shortcuts: Ctrl $+$ I $+$ E $($PC$),$ Cmnd $++($Mac$)$