The two images below are a view of a British online newspaper without Pi-Hole and then Pi-Hole active to demonstrate the reduction in internet traffic you will experience if you implement Pi-Hole. By reducing what your internet connection has to download, you are, in effect, speeding up the downloading of the content that you do want to see.
With Pi-Hole enabled, the images adjacent to the article and just above it disappeared.
It is possible to run Pi-Hole on a Pi Zero or better the Pi Zero 2 W In its simplist form the Pi Zero will need a TF card with Pi-Hole image on it and a power supply, this would be a Wi-Fi connection to your router.
We prefer most devices to be hard wired into our network, so we are using an old RPi 3B, Pi-Hole doesn’t require very much in the way of resources to run, so even earlier models of Pi should be fine. Our reason for not using a Pi Zero is they do not have an ethernet port as standard.
There are lots of guides on how to set up Pi-Hole online, just do a search. It is a low cost and effort way of squeezing a little more out of your internet connection.