Can I change the address on my PayPal account to another country?

No. The laws applicable to PayPal accounts differ by country  and regions. So, you can't change your address to a country that is different from the country you used when you opened your account. If you're moving abroad, you'll need to close your existing account and open a new account. You can have 2 PayPal accounts, so long as only 1 is a business account, if you maintain residences in 2 countries.