How to create a password that is difficult to crack? How to store passwords securely?
How do I create a strong password?
Creating a strong password is very simple, follow these simple rules:

the minimum password length is 9 characters. The longer, the more reliable. After all, in order to choose a password, it is necessary to sort through all possible permutations of characters in the password. And the possible number of permutations for a password of 9 characters is 362 880 (9!=362 880). That is, 362,880 attempts to enter a password must be made in order to find a password, and many servers block access after 3-5 unsuccessful attempts to log in to an account. So hackers will have to pick up a password for a very, very long time, and during this time you will have time to change it, or the server will detect a hacking attempt and take action. A password of 10 characters is even more reliable (you need to sort through 3,628,800 passwords)!
in the password, be sure to use numbers, letters in different registers and punctuation marks (or if they are prohibited by the server, then other alphanumeric characters). Using a regular exclamation mark in a password or an underscore significantly complicates the password and increases the number of permutations. Here is an example of a good password: McT64,13i!
do not use any words that mean in English in the password, as well as Russian words with the English layout enabled. Such passwords are easy to crack. Also, do not mention names, dates, phone numbers, car numbers and other well-known information;
change your password periodically. If the password is reliable, then you need to change it every 3-12 months. The more often, the better! Some mail services report from which IP address the last login was made. If the last login was not from your IP address, it means that your account has already been hacked, and it's time to change the password, as well as make it longer and change it more often.
That's it! Do you see how easy and fast it is to create a strong password? Don't be lazy, please!

How to securely store strong passwords)?
To begin with, let's look at the most unreliable ways to store passwords.

The most unreliable ways to store passwords:
on a piece of paper glued to the monitor;
in a text file on a computer;
in a password-protected Excel spreadsheet (easily hacked);
saving passwords in the browser (spyware easily calculates them).
Secure ways to store passwords:
in a text file or Excel spreadsheet encrypted with VeraCrypt (read the article How to securely encrypt the contents of your computer?) or located on an encrypted medium
on a USB flash drive that you put in a safe or other equally reliable place;
in special free programs with open source code (open source code guarantees the absence of "holes", since if there were, then everyone would quickly find out about it). Here are links to the official websites of these programs (download them only there!):
KeePass Password Safe is my favorite, free, reliable, open source, but in English and there is no support;
Secure Data Manager is an alternative free, reliable, open source, but also in English and there is no support;
RoboForm – this oldest password manager is considered the number one password manager in the world, it is recommended by all the world's leading publications: Bloomberg, The Wall Street Journal, The New York Times, PC World, and this is not a complete list. It's like a Mercedes among cars. It costs 895 rubles a year. There is a free version, but it only works on one device. If you need this password manager to be able to be used on many devices and synchronize them with each other, then you will have to pay(.
I have tried a lot of popular password managers in my time and have been using the free KeePass Password Safe for many years, and although it is not perfect, and it has drawbacks that I don't like, for example, I have to pervert to synchronize between different devices, I haven't found a better one for myself yet.