help to understand a simple electronic circuit, then to improve it

hello

i am trying to understand how an electronic circuit works, and what it does, what it produces.

i have only a basic understanding of electronics and of components...
i have managed to draw a schematic, with a photo of each component, and how they are connected to each other.
i need help to understand what each part of the circuit does, and what it produces (output).

here is the handdrawn schematic : http://rd-stuff.fr/temp/mae-handdrawn-schematic-20240120.png

your job, if you accept it, will be :
- to help me to understand what each part of the circuit does and what it produces (ouptut), and also to correct it if there is an error somewhere.
- to provide a simulation of the circuit in your favorite simulation software (i use everycircuit.com) (a few screenshots or a short video capture, with written explanations or with spoken explanations, is enough)
- to provide a list of the components necessary for this circuit.
(so your bid and proposal is for that)

once all these steps completed, i will release the milestone.

and after that we will discuss for others steps / milestones, because i need help to create a similar circuit, with some modifications, according to my needs.
but i prefer to work on one small step / milestone at a time..

if you have a question, don't hesitate to ask...

thanks for your interest in this project,
regards,