In D&D 3.5, can I acquire a metamagic feat at lvl 1? I'm wondering this because I am playing a cleric and would like to get Empower spell to increase my healing to my party
You can get it but you can’t use it (Empower Spell, anyway).
Empower Spell makes a spell take up a spell slot two higher than it normally would. Even if you applied it to an orison, or 0th-level spell, you’d need a 2nd-level spell slot to cast it. As a 1st-level cleric, you don’t have any of those, you only have 0th- and 1st-level spell slots.
You could take some other metamagic feat, that either increases the spell level by 1 (e.g. Extend Spell) or not at all (e.g. Energy Substitution). A +1 feat could be applied to orisons, which would have to be cast from 1st-level spell slots, while a +0 feat could be applied to 0th- or 1st-level spells. Or you could take Empower Spell now, in preparation for becoming a 3rd-level cleric, if there was some feat you want that you can’t take until 3rd level.
But Empower Spell works very poorly with healing spells. Empower Spell only affects rolled numbers, but all of the cure spells have very few dice relative to, say, damage spells. Compare cure light wounds (1d8 + level) to burning hands1 (1d4 × level): at 5th level, when you would have the 3rd-level spell slots to use Empower Spell with either, cure light wounds is healing 1d8+5, while burning hands is dealing 5d4. Empower Spell offers far more bang for your buck on burning hands than it does on cure light wounds.
Actually, to take this a step farther, healing in general is pretty weak in 3.5. Until you get the heal spell, which is quite potent, healing spells are too weak and slow-to-use to be a good choice in combat, barring emergencies (e.g. someone bleeding out). Instead, buying a wand of cure light wounds or wand of lesser vigor and making sure everyone is topped off tends to be a far more effective strategy. In combat, your actions are better spent killing enemies: you’ll prevent more damage than you would ever be able to heal.
1 Note burning hands is a sorcerer/wizard spell, not a cleric spell. A cleric could get it from the Fire Domain, though, and it was the first thing to come to mind as an example. The Fire Domain is not recommended though.
You can take a metamagic feat at lvl 1, but you like won't benefit from many of them. Empower Spell is such a case, because Empower Spell requires you to place any spell you prepare with it at a spell slot two levels higher. You can, however, combine Empower Spell with Divine Metamagic to apply metamagic feats to your spells on the fly without increasing their spell level.
However, I think it should be pointed out that healing is generally viewed as unoptimal as it is often better to spend your actions subduing your enemies rather than healing. Some other good metamagics to consider combining with Divine Metamagic are Persistent Spell and Quicken Spell. These metamagics can be combined with a myriad of spells that can serve to buff and protect your allies rather nicely. This is considered to be a better use of your actions during combat.