Okey I figured it out
it should be wrapped by

	<cert>
			-----BEGIN CERTIFICATE-----
			
			-----END CERTIFICATE-----
			</cert>
			<ca>
			-----BEGIN CERTIFICATE-----
			
			-----END CERTIFICATE-----
			</ca>
			<key>
			-----BEGIN PRIVATE KEY-----
			
			-----END PRIVATE KEY-----
			</key>

Now the OpenVPN is connected with tun
However, with tap, it shows connected but I can’t access to Internet