cd project_name
python3 -m venv venv
source venv/bin/activate
pip install -r requirements.txt
then, change db file path in SQL_ALCHEMY_DATABASE_URI params of .env file so it matched your current directory
SQL_ALCHEMY_DATABASE_URI=sqlite://///home/ncson1/project/flask-project/flask-api-tutorial-2/src/bookstore.db
flask db init
flask db migrate -m "Initial migration."
flask db upgrade