The rule about making plural nouns is pretty simple. Look at these two pictures and say, which letter makes plural nouns.
Another very important rule you need to know is that we never have the letter ы after these letters:
к г ш щ ж ч х
So what should we do in case if a word ending in one of these letters? For example:
банк – a bank
парк – a park
гараж – a garage