Usually people make a thread in the forums offering to review someone else's first chapter or first few chapters in exchange for them doing the same for your book. It's as simple as that.
I would be okay with doing a review swap of our prologues and first chapter. Here's the story I wouldn't mind you looking at.
https://www.scribblehub.com/series/...-case-of-an-accidental-time-traveler-volume-/
How you leave reviews is up to each individual though so one person may write 5 paragraphs with 3 stars while another might just say it was a fun read and leave 5 stars. I will be more critical but I will be giving more constructive criticisms that will hopefully help with future edits. I hope this helps and will try to leave you a helpful review by the end of tomorrow.