Load Balance between two APs

I have two AP’s in my main office, which i a large open space. I have been having some issues with users being connected to the wifi, but not having internet access. I think part of the reason is that the vast majority of devices seem to be attaching to only one of the APs. How can I adjust that? Is there a load-balancing option in the config? Also, these AP Ones are at least 6 or 7 years old. Should I upgrade them for performance sake?