[DanBC]

Password crackers will use a "dictionary" - a list of words.

Dictionary building software can create lists of words with those common substitutions. (swapping uppercase for lowercase, or subbing certain numbers for letters, etc.) They can also add numbers to the words.

Ideally, use a good diceware phrase to secure a password safe. Then use the strong password generation features of that password safe to create all the other passwords you need.

(You can write the diceware passphrase down if you need to while you're learning it. Just treat it like high value currency, and destroy it when you've learnt the phrase.)

Access control is a problem waiting for an easier solution.