Are password managers used?

[SenseiiPikaa]

Hello friends, up until now, I have never used a password manager. I only saved my password in my browser when it asked me if I wanted to. For passwords that are not stored in my browser, I save them in a channel I created on Discord. Each of my passwords is very long and complex. What do password managers do? Do they securely store passwords automatically and fill them in when needed? Also, I would appreciate it if you could tell me if this is necessary.