If you are looking for a single word, verbalize works: -
- To express in words: He couldn't verbalize his feelings.
The computer will verbalize whatever text you typed (out loud).
There is a conflict of tense in the example sentence, I would rewrite it like the example that follows. As we are using verbalize, "(out loud)" is redundant I would say as common usage of the word relates to the spoken word.
The computer will verbalize whatever text you type.
Literally however, the definition can be used in non spoken context, as the Google definition implies: -
express (ideas or feelings) in words, especially by speaking out loud.
"they are unable to verbalize their real feelings"
speak, especially at length and with little real content.
"the dangers of verbalizing about art"
If you wanted to draw attention to the fact the computer is speaking "out loud" I would move this closer to the verb, and use aloud instead, like this: -
The computer will verbalize aloud whatever text you type.