Fixing my website for third time

Hello everyone. My wp website was penalized a few months ago( when I type my website in browser it appears in serp with some categories but when i type website and some post kw it doesn't show anything). I want to change my website and fix gsc errors. First of all, I want to remove post tags from wp posts. How to do it in the easiest way and what should I do when the errors appear in gsc(because of removing). I also want to change the theme and structure of my website(I know it's gonna be messy). If you have any advice I will appricate that. Thanks in advance.

As you say your site is penalized so I can assume your site once ranks well.
Post tags, theme and structures are less likely to be the cause of "penalty".
Show us your site so we can know the main issue.

Well I have about 30 posts with sh*** content and Im aware of it. I was penalized few years ago and after 2 months the website came back itself with good serp positions. Then i change the theme and drastically change the look of entire website, few days after- penalized again. Now I want to improve my articles and change the theme again to make simpler look.