The words too and also generally do not need commas with the exception of also at the beginning of the sentence.
Historically too and also had commas before them at the end of the sentence. Since the words are just plain adverbs, there was never really a need to use those commas. They have been dropped — many years ago, in fact.
…She was in the room at the time too.
…We need another copy of it also.
In the middle of the sentence, too and also are simple adverbs, and there is still no need for commas.
…He too needed to complete the project.
…The contract also needs to be read.
Though too would rarely be used at the beginning of a sentence, if it were, it would not take a comma after it.
Also, on the other hand, when it occurs at the beginning of a sentence, is a conjunctive adverb of more than one syllable and needs a comma.
…Also, we will take a look at his health.