

Ctrl+ r followed by =12+1012 and then Enter key inserts 1024.Ctrl+ r followed by = allows you to insert the result of an expression.Ctrl+ r followed by a inserts the content of "a register.Ctrl+ r followed by % inserts the current file name.Ctrl+ r helps to insert the contents of a register.Indentation depends on the shiftwidth setting. 0 followed by Ctrl+ d deletes all indentation in the current line.Ctrl+ o followed by 3j moves the cursor three lines below.Ctrl+ o followed by A moves the cursor to the end of the current line.Ctrl+ o execute a Normal mode command and return to Insert mode.See :h 'complete' setting for customizing autocomplete commands. See :h ins-completion for more details and other autocomplete features. Ctrl+ y or Enter change the autocompletion text to the currently selected item from the popup menu.you'll retain the text you had typed before invoking autocomplete.You can also use Ctrl+ l to move up the list. You can use ↑/ ↓ arrow keys or Ctrl+ p/ Ctrl+ n to move through this list. If more than one line matches, they are displayed using a popup menu. Ctrl+ x followed by Ctrl+ l autocomplete line based on matching lines in the backward direction.Or press Esc to select the first match and go to Normal mode. If you were satisfied with the first match, typing any character will make the popup menu disappear and insert whatever character you had typed. You'll have to press Ctrl+ y or Enter key to choose a different completion text. With multiple matches, you'll notice that the first match is automatically inserted and moving through the list doesn't change the text that was inserted. If more than one word matches, they are displayed using a popup menu. Ctrl+ n autocomplete word based on matching words in the forward direction.Ctrl+ p autocomplete word based on matching words in the backward direction.

Ctrl+ u delete all the characters before the cursor in the current line, preserves indentation if any Autocomplete word.Ctrl+ w delete characters before the cursor until start of a word.

#Vim delete line manual
:h insert.txt - reference manual for Insert and Replace mode.:h usr_24.txt - overview of the most often used Insert mode commands.

There are also commands available for moving around, deleting, autocompletion, etc. This is the mode where the required text is typed.
