There are 4 main websites that contain record collections from around the world, and also guides to help you with your family history research. They also have User submitted family trees. These are FindMyPast, Ancestry, My Heritage and FamilySearch. FindMyPast and Ancestry require a subscription for most of their record collections, while FamilySearch is free.
So, which subscription site should you use? I personally prefer Ancestry, because they have the most records for where my ancestors have come from, that aren’t available on free websites. I generally sign up to use FindMyPast on a pay as you go or a month at a time, to access records that aren’t available at Ancestry. I was offered 75% off My Heritage at the end of last year (December 2019), so I currently have a subscription, but I have found there are very few collections that are unique to My Heritage, and a lot of the collections are available on free websites
Each week, I do a Friday Finds post, to list the new and updated record collections. You can find these by selecting Friday Finds or the website from the Categories.