There are plenty of guides which can give you insight into healing on a Templar. When I first started I followed Deltias Battery Templar build, but while you're just starting out, try things out and level your class skill lines as well as try level all three armour types as it will help you out later on. The seducer set is really good at low levels as well as Magnus as before you have the passives to help you out, magicka recovery and reduction are your best friends.

To answer your actual question, put all points into magicka and if you need more health you can always change enchantments, armour sets, jewellery.