You have 30 days from the date you were served with the summons and complaint to file an answer. The answer must be filed with the Court Clerk with a copy mailed to your spouse's attorney (or to them if they are acting as their own attorney).
If you do not file a response, your spouse can get a judgment in default entered against you, and your spouse/their attorney are not required to give you any notice or an opportunity to be heard by the Court when they request the default judgment.
The judgment can be for the divorce itself, of course, but also may affect any property rights you may have, require you to pay some debts, or require you to pay child support or alimony.
It is best to file an answer. If you file an answer you can settle the case by signing a consent decree with terms you agree with, or if you cannot agree you will at least be entitled to notice of when a hearing is scheduled so you can at least be heard by the Court.
First let me extend my sympathies. It sounds like this is happening at an especially tough time.
You should be able to find some type of free legal assistance through the legal aid services in your state. Here's a link to Arkansas Legal Services. They should be able to help you. http://www.arlegalservices.org/
I'm not sure if there are other service in AR, but if there are the Arkansas State Bar Association would probably be the best place to ask. Just google "Arkansas State Bar" or "Arkansas Bar Association".
I wish you the best of luck.
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