You need charge VAT to all EU customers, unless these are companies with VAT Number, in theses cases you need ask for the VAT number and valid it via vies website VIES
You do not charge VAT to all customers outside of EU, in theses cases theses customers are exempt from VAT.
When you buy in EU, you are free of VAT when you provide your number VAT to the sellers.
When you buy from outside of the EU, you are free of VAT.
You do not charge VAT to all customers outside of EU, in theses cases theses customers are exempt from VAT.
When you buy in EU, you are free of VAT when you provide your number VAT to the sellers.
When you buy from outside of the EU, you are free of VAT.