>>76333555 (OP)i had this when i started
you can avoid this by grabing the bar differently
don't grab the bar directly on your palm, because it will put the top pillowed part of your palm on top of the bar and get pinched with your weight, you will get blister and worse like your picture
instead grab the bar from the bottom of your fingers and push your hand forward, this way the pillowed part of your palm will go behind the bar and won't be pinched
this was a game changer for me because getting blisters were holding me from doing more chinups