So when using password managers do they automatically record data when you fill in fields or do you tell it to record and save some sites?
I don't know about the others, but KeePass doesn't have a "record" mode. It is basically just an encrypted database file... you need to create new entries (bank, school, Amazon, email, etc) and you enter the URL for the login page, the username, the password, and any relevant notes (like security questions). Its best to store https secure URL's if they are available.
Inside the database, you can create categories/folder to help with management... like Banking, Shopping, Websites, etc. Or, if you prefer, you can keep a number of totally separate databases.... which will require a totally separate password to unlock each database too. I wouldn't personally make too many because of the difficulty in remember really strong passwords that you should use as a Master Password... but I can easily imagine a separate database for "Work" versus "Personal" for some users.
Once you create some entries, the operation is simple: Click on an entry you wish to log in to, hit CNTL-U (for URL) and KeePass will open your default web browser and take you to the site. If the browser is already open, KeePass will open a new tab instead. Then there are 2 ways to use KeePass to enter your login info... 1) drag and drop the ******* info from the KeePass window into the page you want to log into.... or 2) Click the KeePass entry to be sure it is highlighted, hit CNTL-B to capture the username, then click into the web page username box and hit CNTL-V to paste. Go back to KeePass and this time use CNTL-C to capture the password, then click into the web page password box and again hit CNTL-V to paste. There is a security timer built in to KeePass so you have to do these copy/paste operations without a long delay.
There is another feature called "auto type" but I do not use it. There is some risk associated with it from keyloggers.
KeePass (and I'm sure the other products too) has a password generator to help you create difficult strong passwords. You can specify how many characters, upper/lower case, numbers, special characters... even high ANSI characters (which I would probably not recommend in most cases). As you build your database and find you are using passwords that are too short, or insecure.... you can use this generator tool to help you change to better passwords. You'll have to watch the sites you log into, and you'll find that some may only allow 8 characters, and some have other restrictions that you must comply with. The password generator helps you to set those criteria first so that you generate a usable password.
DO NOT LOSE YOUR MASTER PASSWORD TO OPEN THE DATABASE. Other products may have some kind of "password recovery".... but KeePass does not. (I really wouldn't want a company to store my master password anyway!) You should use a strong master password, but if you forget it, there is no way for you to get anything out of the database. You should also make more than one backup of your database.... long story, but I corrupted my working copy and my backup when I first started using it, so I had to rebuild the entire database again from scratch. Not fun. Final comment... KeePass will also let you export your information to a CSV file that you can open with Libre Calc or some other spreadsheet program.... this is handy to clean up a little and print a hard copy of the usernames and passwords.... but of course it should be kept in a very secure location! But a hard print copy is a final backup for you also.
Cheers!