Who can say what method can make a person's voice louder?

The landlord can find a book and read it for half an hour every day. Pay attention to reading as hard as possible and speak fast, whether at home or in the street. It will take about a week to take effect. I used to have a low voice, but I got better after using this method. This is just a suggestion.

Another one, I think we should improve our self-confidence in speaking in front of people, talk more and keep in touch with others. I hope it helps you.