Checkbox in Microsoft 2016

I made an excel file last night (with checkboxes) using Microsoft 365. But now when i open it in the office PC using ms excel 2016, all the checkboxes are gone and displayed with 'FALSE'. How can I insert checkboxes now with this version? If I use checkboxes via Developer Tab, how can I adjust its size and stick it inside the cell? Thank you, hope you can help me.