Hi @ErinOFlaherty7 - With the default forms code with in 6.3 you should be able to submit a form, ideally it should not have any issues. If you have any, can you be more clear with error details and screenshot.
In addition to what we have in the default AEM instance, we can install the forms product with reference from this link -
AEM give OOTB forms , using which form can be submitted too. These component should be available in /apps/core/* . Using this forms , you should be able to submit a form. I am not sure about your requirements whether it requires adaptive forms or not , else OOTB can be leveraged.
For using adaptive forms ,additional licensing is required.