It is important that you find the right agent or publisher to handle your work.
There's some good advice from Lisa Jewellon this subject.
The most commonly recommended source of information is The Writers and Artists Handbook. Click the image below and you can buy a copy right here on this site.
However, I have found that the great majority of this information is also available on line at FirstWriter. The main advantage is that you can enter the genre of your work, choose the countries you want to be published in and one or two other criteria, and you are given a list of agents/publishers to match your requirements.
An additional benefit is that you can click straight onto the appropriate website where you can find out more about your chosen agent/publisher including their instructions on how to submit queries and mauscripts to them, as well as feedback from other users.
Again, it's not free, but the membership fees are realistic. You can sign up for just one month to try it out.
