Use privacy browsers like Brave or Firefox Focus, or use incognito mode on Chrome or Safari.

Search with Duck Duck Go, which says they don’t use your info. Perhaps.

Don’t buy anything online.

But remember that even if you never go online again, your bank, the places you shop, the governmental agencies you interact with, the documented web of your life; all that IS online.

Even if you lived in a hut and stashed cash in your mattress.