Use of analog multiplexer with esp8266 and blynk

I have a question regarding the use of an analog multiplexer and how would I read the data in blynk knowing that the esp8266 only has one analog input, and with the multiplexer I have several analog outputs connected to a single one of the esp, how to display several values that help me give the reflected sensors on blynk

Do you mean inputs?
If not, then how are you hoping to read these outputs?

I’d suggest that you start by getting your multiplexor working without Blynk, giving you the right readings in the serial monitor. Adding-in Blynk will then be much more straightforward.

Pete.