tons of alternatives.
search engines with independent indexes(i.e., not beholden to any big search engine):

• mojeek
• brave search(semi independent)
• kagi(semi independent)

meta-search engines(gets results from other search engines):

• startpage(google)
• duckduckgo(bing)
• qwant(bing)
• swisscows(bing)
• metager(multiple sources)
• searx(ng)(multiple sources, configurable by user)

I'm still missing a ton but this should give you an idea.

for more, see this interactive graph, or this Wikipedia list which includes other niche types of search engines as well.

I personally use mojeek(because of their independent index) with duckduckgo as a fallback.