You can simply run the following command in your terminal:
ps -ef | grep mongod | grep -v grep | wc -l | tr -d ' '
This command will show you various processes run by mongodb.
And if you want to see the status of mongodb then just write the following command in your terminal, this will show you the current status of mongo.
mongo
If you want to learn more about MongoDB then go through this MongoDB course for more insights.
MongoDB is an important part of full-stack development. Enroll in this Full Stack Developer Training to start your journey in this field.