"LOOK UPON THE FACE OF YOUR NEW POPE. HIS HAPLOTYPE IS IRRELEVANT. HIS PERUVIAN HERITAGE ASIDE, LOOK INTO THE EYES OF A CHICAGO SPORTS FAN AND KNOW THAT HE HAS SUFFERED LIFETIMES OF ANGUISH. THE FAILURES OF THE HAM SANDWICH RACE PALE IN COMPARISON TO THE 'DOUBLE DOINK', THE BULLS AFTER THE YEAR 2000, AND THE UNSPEAKABLE TRAUMA OF BEING A CUBS FAN. KNOW THAT I DO NOT SPARE HIM THE JUSTIFIED TRUTH ABOUT HIS GENETICS OUT OF CONCERN, BUT MERELY RESTRAINT; THERE IS NO ADDITIONAL MISERY I NEED TO PLACE UPON A CHICAGO FAN, IT WOULD MAKE ME SEEM WEAK AND OPPORTUNISTIC... LIKE YOU, HAM SANDWICH."
You can, but it's not an exact science. Any responsible anthropologist calls it a sex estimate because it's not a sure thing. Broadly speaking biologically male skeletons tend to be more robust than biologically female skeletons but there are plenty of exceptions to this "rule".
Edit: ideally you'd also be using other methods for sex estimation and comparing all your results. It's still just an estimate if course because there's plenty of room for interpretation of skeletal remains. Plus obviously biological sex ≠ gender but that should go without saying