Have you tried searching for agents on QueryTracker and Manuscript Wish List (MSWL)? Also, Jessica Faust of Bookends Literary has many YouTube videos full of wonderful advice. She also has a blog on Bookend's website that has lots of great advice and information.
Getting an agent is really hard because literary agencies average thousands of queries every month. Agent Sara Megibow says she gets about 25,000 queries a year and out of that offers representation to maybe 5 to 7 new clients. That's the kind of odds we're up against.
After 3 years of writing, writing 8 novels, taking numerous writing workshops, and sending out around 300 queries, I finally landed a contract with ?The Wild Rose Press for a historical romance. There are publishes like TWRP that accept unagented manuscripts. I had sent out 51 queries on this manuscript and it got rejected 50 times. TWRP was the 51st query. The agent I queried just before querying TWRP responded with advice on why my heroine was unbelievable and how I should rewrite her. I started to follow this agent's advice and after 9 pages of rewriting, I realized my heroine was no longer the person I wrote and loved. So I sent that rewrite to the trash. TWRP liked my heroine just the way I'd written her.