16ch relay module project with mcp23017

[esptita]

hello I hope to be in the appropriate forum.
I am an apprentice, I only have knowledge of electronics, but nothing of programming, I happened to tell you about my project for my house.
Now I have the mcu8266 module + esp easy firmware + pca9685 module + 16ch relay module + app inventor working on my local network, everything works perfectly both from the web browser and also on my cell phone, now what I want is to be able to have manual control through switch or light key buttons as in what we all have in our homes, to control the on or off of the 16 relay, I understand that I have to use the mcp23017 module as input for the 16 switch buttons, I understand that I have to send the signal GND through the switches (serial circuit) to enter or close circuit to each pin of the mcp23017 module.
1 how do I have to connect the two modules pca9685 and mcp23017, making the SCL and SDA pins parallel?
2 How do I integrate the mcp32017 module into esp easy?
I leave an image of the elements that I am going to use and if you can help me in how to connect electrically and in the programming, thank you very much in advance.

[Ath]

Mostly answered in your other thread: viewtopic.php?t=9065
Let's continue the conversation there.