I have a list that I am wanting to limit what users can do. Is there a way to allow users to enter information into the list and not add/modify new list fields or views?
Yes. That is possible. You need to create custom permission level with below steps:
1. Go to your site. 2. Setting -->Site Settings -->Site Permissions -->Permission Levels -->Add a permission Level 3. Give a name to your new permission and select appropriate permissions from "List Permissions" section based on your need.