In microsoft word when I write a word in front of another or try to fix a word it erases the letter in front of it.

..click insert....

insert, right above the delete button

click the insert button on your keyboard
(insert or replace)

Press insert above the delete button lol.

Another simple way is to click that place and press enter.
The next word goes to next line.
Now do what you want. Then click delete and get those back in place.

What they said lol

press 'insert' on your keyboard and try it now.