Did you upgrade the driver of the network adapters after new operating system installed? Perhaps this is a compatibility issue between the network adapter and windows 10.

No special settings related. You may try another port , another Ethernet cable and a different PC, restart/reset the PC and the router. Update PC's network adapter driver and check the PC settings...

TL-WA901ND is not a router but an access point. Access point has no PPPoE connection. You might buy a wrong product.

AP mode can't use home care. it is better to use the first deco as router mode. The second deco should be connected behind the first deco. Like this: ISP modem- switch- deco1-switch- deco 2 -deco 3

is your issue solved?

You may check in the router's admin page to see whether it have the option for Access control. If it does, then you can try to set it up for your purpose.