How can I enchant items in Elder Scrolls Arena?
To answer your title's question, you don't enchant items as far as I can tell like you would in other TES games like Morrowind or Oblivion, but you can purchase them. As was already pointed out, everything except leather/chain armor can be enchanted.
I can't find anything that tells you how to enchant things yourself, just where to buy them all.
If you open the wiki link listing all the enchanted items, you'll notice it just lists the costs and the locations you can buy them; Further supporting the thought that you can only buy these items not enchant them yourself.
Dwarven - 1250 Skyrim - Amber Guard - Mages Guild
Dwarven - 1250 Skyrim - Amol - Mages Guild
Also in this thread they only mention buying enchanted items, not creating/crafting them.
"If I buy a "Sword of Life Steal"..."
Also from another Elder Scrolls Wiki (Bold mine):
"Your body is protected by various pieces of armor you can find at an equipment store."
Also see the same wiki's enchanting page, the only Elder Scrolls games with enchanting articles are:
Enchant - A skill in The Elder Scrolls III: Morrowind
Enchanting (Oblivion) - Enchanting items in The Elder Scrolls IV: Oblivion
Enchanting (Skyrim) - Enchanting items in The Elder Scrolls V: Skyrim
Enchanting (Online) - Enchanting items in The Elder Scrolls Online