is there any lib available for converting a text to voice
Google gave these results.
In the past day or so, you have repeatedly posted several vague, very generic questions that don't really relate to Rust programming and show no effort toward a solution on your part. Please, refrain from spamming the forum. It's not possible for us to help you if you don't approach a specific problem with at least some actionable details.
Since I was curious, I looked into this a bit more. deepspeech-rs was initially exciting, but it took me a while to realize that it's actually a speech recognition library, not a voice synthesis library. google_speech might work, but it's calling into google servers, not doing local speech synthesis.
It looks to me like there are no well-maintained local speech synthesis/voice to text libraries in Rust. The closest is espeak-sys, but it hasn't been updated in 4 years and it's raw C bindings.
The closest thing I found in general was CMU Flite, a small speech engine written in C, aimed at embedded devices. It's not a rust library, but it should be very possible to write Rust bindings to flite! That would be a large undertaking, but if you want to do it, the nomicon would be a good place to start: https://doc.rust-lang.org/nomicon/ffi.html.