Looking for TTS App/Software for Nonprofits & Community Web Development

Hello to everybody from Minnesota USA

Big question any input and direction is helpful.
Clarification may be warranted.

I want to add a TTS to a new community website I am building.

The main goal here is to have the read aloud button along side the topics or paragraphs where-ever possible.

I am looking for either affordable TTS applications or companies that will hand out TTS software/app for the purpose of helping the disabled.

I’ve been searching around a tiny bit.

“Free Text To Speech programs for nonprofits and community web development projects to help the disabled listen or read”

Anyone around