I have 400+ logins. It's a hectic task to manage all those logins and keep them safe. I used to use the browser's default password manager to store all of those logins, but it wasn't that effective, plus it wasn't that secure either.
I had heard and known about password managers—tried a few of them but couldn't continue because most of them were paid services. And I didn't want to pay for just another online service.
Two years ago, I learned about Bitwarden, which is a free password manager and is open source as well. I transferred all of my passwords into it and have been using it since then. It's a decent password manager. It's available on almost all platforms.
The best thing about password managers is that you only need to remember one password—for the password manager itself—and it'll take care of all your other passwords.
Now, you might say that I don't want to be dependent upon a password manager—which was my line of thinking before using a password manager—but you see, when you have too many logins, it's nearly impossible to remember all those logins.
If you think that you can use the same password everywhere, then you're wrong. Doing so can jeopardise your whole online presence. If someone gets the hang of your password, then he basically has access to all your accounts online. That's why it's recommended to use different passwords on different sites.
Most of the password managers come with a password generator as well, so you can generate a random password and use it—the password manager will keep it safe.
I personally use Bitwarden because it's free and open source. I have tried other paid options too. Personally, I liked 1Password, LastPass, and Robo Form.
It's a good idea to start with a free password manager, and later, if you want, you can switch to a paid one.
The gist is: use different passwords for different accounts and use a password manager to manage them and keep them safe.