Hello!
Let me see if I understood:
I will mow the lawn myself.
So, you want to now what kind of word is "myself"? It is an intensive pronoun.
Intensive pronouns are identical to reflexive pronouns; however, intensive pronouns place emphasis in the sentence, like in this case. I will mow the lawn MYSELF: I will do it on my own; I do not need help.
Hope this helps.
