Disclaimer: I am no expert by any means.
With that being said, as others have said, a DNS is like a phone book. By using PiHole with it going to a privacy respecting DNS service, you in theory eliminate being tracked by a DNS provider, but you do nothing to prevent your isp from tracking which ip addresses you access, and you do nothing to prevent search engines tracking which results you click on, you do nothing to prevent your web browser from tracking your browsing (especially on Chrome and Edge).
In summary:
DNS lookups: yes
ISP with IP addresses: no you would need a GOOD VPN or TOR and either one properly configured
Web browser: no, you need at least Firefox with data collection turned off, preferably with something like ublock installed.
Search engine: no, requires more research but supposedly duckduckgo and eccosia are privacy respecting *citation required
Step 1. Never connect it to the Internet. Step 2. Connect Linux machine. Step 3. Profit.