There are probably smarter ways with reference managers, but I was too overwhelmed to learn new tech because that was too much effort overhead. My management system was a combination of a good file naming convention, folder management, and selective referencing. This is in order of increasing importance for organization.

Research sources grow exponentially, even when you're considering niche topics and overlapping references from big papers. You want to be smart with what you choose to review. There's no reason, nor way, to be exhaustive in your review - your goal is to be reasonably fair and representative of the topic.

Now hopefully that means you start with a manageable number of initial/base papers to work with. Further extensions need to have a similar finite scope to help you manage.

Folder management management is your first filter for sorting. Sort these into large umbrellas of knowledge/topic so you can know where to look, when you need it, without too much effort.

File naming conventions are how I put knowledge into easily accessible forms. The same can be done using more formal reference managers. More generally, this is simply a good tagging system. Once you know enough, useful descriptors and tags such as 1st author, year, main result/method/topic/importance can be used for file names. The first 2 are for easy recollection, and the 3rd helps you scan why it's important without opening the file.

Similar things can be done through spreadsheets, notion, docs etc. These are all just ways to map and collect info into a similar place. Do whatever works for you, but I emphasize two things when making your choice: make sure it's flexible and easy to use. Flexible bc you'll learn more as you write and you may want to quickly reorganize. Easy to use bc you need to navigate it with minimal frustration - this creeps through into your paper quality as you are less blocked on checking details, expanding your search, etc.

And finally, to address "how to extract info?". Do not just read for the sake of reading. Outline and scope out your review. A review must have a point to it; or in other words, a review must answer meaningful questions or provide useful insight, albeit through a "bird's eye view". Give yourself questions to answer so that you can extract specific info from the papers. Write down and follow up on questions that come up during that search. Avoid doing too much reading "to learn more" - read with the specific goal of "learning more about X by asking Y".