@DSER To add to the above. For connection type, see Step 11 from this FAQ: How to use Deco with your existing router

@DSER 1. TP-Link Deco mesh WiFi will not join Archer AX2300 WiFi. After configuring Deco mesh, you will need to turn off WiFi in Archer AX2300, otherwise you'll end with two different WiFi networks...

@HustiUK TP-Link Deco does not support OneMesh. See this document for more info: TP-Link Deco Mesh vs EasyMesh vs OneMesh vs Omada Mesh What's the Difference?

@DukeCaboom Deco M4 have gigabit Ethernet ports. They should be able to handle gigabit speeds, wired. Their WiFi speed will be about 500-600Mbps in ideal conditions. This is as much as WiFi5 can...

@Balaji817 Yes, this should work just fine.

@palcouk Epson WF-3820 description says it has Ethernet port. Try connecting Epson WF-3820 with Ethernet cable to one of available ports of Main or Satellite Deco, and see if you can configure it...