Can i download esr on my linux 32 bit

https://support.mozilla.org/en-US/kb/firefox-has-ended-support-32-bit-linux

Mozilla dropped support of 32-bit Linux from Firefox 145.0 and later.

You can use the Firefox 140.0esr currently at 140.12.0esr and the last planned update will be Fx 140.15.0esr on September 15.

To download the current 32-bit Firefox 140.12.0esr tarball https://www.firefox.com/download/all/desktop-esr/linux/ > pick a language then [Download now]

it would be helpful to know if there's still an ESR build available.

Did you miss my reply above? as the now older Firefox 140.0 esr (currently at Fx 140.13.0esr) is an option as Mozilla dropped 32-bit Linux support starting Fx 145.0 and later. So there is no 32-bit Linux versions for the current Firefox 153.0 ESR from Mozilla.