I believe all you have to do is set up an event that passes the value in the text box into a variable.
pseudo code e.g. "on keyboard:shift.pressed >> system >> set value
select the variable e.g. worldName1
set the value e.g. str(yourTextBoxName.Text)
::: the str() converts the text into a string value. You could use str() if you wanted your worlds to be named using words.
int() / float to convert the input to an integer or floating point value! For naming worlds with numbers.
From there you can use the general text object to render the text on canvas: e.g. Add event: system >> every_tick >> set text >> "This world is called "& worldName1