Site infected with SEO Spam

Carefully follow https://codex.www.ads-software.com/FAQ_My_site_was_hacked

Then take a look at the recommended security measures in Hardening WordPress – WordPress Codex and Brute Force Attacks – WordPress Codex

If you can’t do the work yourself, consider looking for a reputable person on https://jobs.wordpress.net/ or https://directory.codepoet.com or https://upwork.com

(FYI, it’s not a good idea to respond to work offers from random forum users who have read about your issues.)