Yes, you can amend the list of goods and services listed in your trademark application; in fact, sometimes, the USPTO will ask you to do so in the office action.
The examiner usually raises an issue with the goods and services items if the terms are vague or potentially deceptive. However, there are other cases where you may wish to amend your list, such as when addressing a likelihood of confusion refusal and avoiding overlap with another trademark or when leaving out terms for which your mark would be considered descriptive.
Please keep in mind that having to amend your goods and services may result in loss of your TEAS Plus status as well as a $100 per class fee. If you need to reconsider your list, it's advisable to consult an experienced trademark attorney.