How do I increase the storage on my mac

Follow these instructions: Free up storage space on your Mac - Apple Support

What happened to you is often the result. You most likely need to remove a great deal more data. I recommend that you purchase an external drive and copy files such as music, photos or videos over on to it. Then they can be deleted from your hard drive to clear the needed space. These days external drives are plentiful, cost effective and easy to install with vendor provided USB cables. Sometimes you may have to reformat it, though. Easy to do and problem solved.

The suggestions which are often made to clear up space typically do not clear enough to be useful, yet people continue to be offered those solutions. Another fact that should be noted is that if a hard drive becomes too full the computer can and will stop working. This can clearly be a serious problem. Adding the external drive is easily done. Glad I could be of service.

Have a look at using iCloud Drive storage which can be easily added at modest cost. It could be particular useful for archiving large files (e.g. media) which are accessed relatively infrequently. iCloud Drive works best over a fast internet connection.

- Pie Lover