If you enchant one of your regular card using a TC Enchantment, then that regular card will now become a non-salable treasure. In this case, it will be possible to keep the enchanted card after battle since it will be in your side deck. Using it will allow it to disappear however since the rules of TC still applies.
Enchanting a card using a regularly trained spell will only work for that battle only.
In all upcoming battles, you'll have to enchant them again.
The only way to have spells pre-enchanted is to use a TC enchant on a trained spell then either discard it (right click) or don't use it in the battle. TC can only be used once. If you use an enchant on a spell but don't use the spell then the enchanted spell becomes a no-trade, no-auction TC and sits in your side deck where the enchant used to be.
There is no way to pre-enchant trained hits with trained enchants. There is also no way to retrieve or keep a treasure card once it has been used in a battle.
There isn't a way to use an enchanted card and keep it after a battle. You can enchant a card with a Treasure Card version of an enchantment, and you keep that enchanted card after the battle if you don't use it.
I enchant the cards from my school deck before a hit. Usually with tough (fist). My deck card comes back as originally given for the next duel. You don't say what level you are, but later in the game you'll get the chance to train for those enchantment cards to keep in your deck. That really helps to have them right there. So I guess the answer to your question is no. Keep asking your questions though. Star Edward and Freshta always have great advice and encouragement.
once you use an spell that was enchanted, it will go away and you will have to enchant another one with another enchant spell
Wolf LegendSword-LvL 125 Wolf LegendSword-LvL 8 Daniel BattleShade-LvL 125Wolf LegendSword-LvL 6 Blaze NightRider-LvL 125 Sloan Bear-LvL 1 Michael ShadowStaff-LvL 125 Marcus WildStaff-LvL 1 Blaze NightFlame-LvL 125 Patrick Star-LvL 1 Carlos GhostDust-LvL68 Blaze MythRider-LvL 39
spell will only work for that battle 
Blaze NightRider
Michael ShadowStaff
Blaze NightFlame
Patrick Star
Carlos GhostDust