“A lot” means a large number or amount. Some synonyms for “a lot” are “many”, “much”, “numerous”, and “plenty”.
“Many” is used with countable nouns. For example, “There are many books on the shelf.” This shows that there is a large number of books.
“Much” is used with uncountable nouns. “There is much water in the glass.” Here, “much” indicates a large amount of water.
“Numerous” emphasizes a great number that is almost impossible to count. “The city has numerous parks.” This shows that there are a very large number of parks in the city.
“Plenty” suggests an abundant supply. “There is plenty of food for everyone.” This indicates that there is more than enough food.
These synonyms can be used to add variety and precision to your language when expressing a large quantity.