Some ways to stay safe on the internet are
Don't share your password with other people. If you do thy can get into your personal accounts and ruin your life. They can also change your password.
Don't give your address to people on the internet unless your buying something from a trusted site. They can come to your house and steal you. Or send a bomb to your house.
Don't download stuff you don't what it does or is. It may have a virus or be a R.A.T.
Don't meet up with people you meet online. They might now always be who they say they are.
Don't put your phone number, email address, address, full name, school etc online. It can ruin your life.