@joyfulnoiseforyahshu were there any other binaries in that folder that started with mongo?
Could you state how you installed the MongoDB package? Did you follow the directions given on the MacOS installation page?
I run MacOS Catalina as well and this is the list of files I get from running that command:
mongo
mongod
mongodump
mongoexport
mongofiles
mongoimport
mongoreplay
mongorestore
mongos
mongostat
mongotop
If you don’t see a list similar to the above then you don’t have a full install of the MongoDB tools.