Can't access nextcloud from LAN

But I think I will have the same problem.

ROUTER
|
SWITCH
|
ETHERNET CABLES
|

  • Dietpi PiHole
  • Computer
  • Router (bridge)
  • TV…

Should not be the pihole before the switch?

Also, can i install Pi-Hole but don´t block anything? There are more people using the network and they wouldnt know how to whitelist something in case pihole block something they need.