ok i have a browser game that im working on, and i would like to know how to code something so i can equipped items to the user so there stats will go up or down based off the item. my datebase is in mysql. so if anyone has any input on this plz let me know, or point me the right way.

Make a row with equippedItems and then just list all the items they have equipped, separated by commas?

You need:

a table of users.
a table of equipment.
a table that links user IDs to equipment IDs

and a join query