Connection to database was done, the files are organizes an ready to use by new tables

one student can take a book in anothers name

Node modules is never pushed never do add . you need to know what are you adding to production

you have nice folder structure its easy to navigate your code according to the need

if something does not work as expected i think it would be better not to add it like the auto complete...

since you havent pick good names that explain it would be nice to have comments your code on autocomplete may be good regarding functionality and efficient but it is definitely very hard to read when you work with teams you have to explain the code and the code flow is it would be nice to have some comments explaining the code .
I want to point out how important is to write readable code it is as important as writing the code itself it is like producing a machine that does something without producing a manual on how to use it...

check if inputs empty before adding new book

Config env shouldn't be pushed to the master it has your params to access database this is a fatal practice

its nice that you have a readme, it made my life easier because it includes running your project instructions .

https://www.1keydata.com/sql/sql-getdate.html

borowing a book gets to a page
is it successful ? did it fail? why go to a broken page?