If you have access to your routers control panel, keep reading: You can change its default DNS to something that blocks ads and malware usally found under Internet -> Credentials -> DNS, though this may vary. Here are the addresses of the DNS i recommend: Dnsforge.
Reboot your router and there you go, now all the devices that are connected to your network can have a sanitary internet experience despite not having any adblockers installed. This is particulary useful for embedded devices like SmartTV and FireTV that don't really let you tinker with them.
Mullvad DNS: A alternative to Dnsforge.
Quad9: Try Quad9 if you wish to block malware, but let ads through.
Want a DNS that lets you set your own rules? Try NextDNS - Cool guide - Attention: Their free plan is limited to 300000 queries per month
Want a DNS server that sits right next to your router without limits at all? Try Pi-hole
No problem: You can use another DNS on your end devices too.
Works with all Wi-Fi connections and mobile data!
If you're on Android 8 or older i recommend [AdAway](https://f-droid.org/en/packages/
This only works per-Wi-Fi unfortunately.
If your router supports Wireguard, and you have stuff like NAS at home, come grab a beverage and sit down. Wireguard is your own and personal VPN tunnel that connects your phone or laptop to your home network, no matter what public wifi/mobile data you're on. It's as if you are at home: You can use your NAS and anything else sitting on your home network worldwide without having to open ports and exposing them to the internet.
Caution: Only use QR code if you can and delete every single config file when everything is said and done. You do NOT want to get them on wrong hands.