Need sensor to control water flow

Hello everyone,
I am working on a liquid monitoring project and in my project I need a sensor that is attached to a liquid container (two valves attached to it) and if the liquid in the container reaches a specific height or value then a specific valve will be opened and the liquid would be released to a sensor that measures its flow.
Can anyone give me any suggestions for sensors which i can use in this condition? and if possible which type of valves can i use?

I look forward to hearing from you all soon.

Based on the information you have provided I would recommend this float switch

Valve.

Flow sensor
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