How can I block ads/trackers?
On a computer such as a Windows, MacOS, or Linux device you can use uBlock Origin to block ads and trackers online.
If you need a system wide ad/tracker blocker use AdGuard. (mobile or computer)
For mobile browsing I recommend you use Mull and add uBlock Origin.
iOS can use something like SnowHaze, or a firewall, but iOS is very limited to effective privacy options.
If you're needing something to cover all devices on your network you could setup a Pi-hole.