PEGI / ESRB game ratings are displayed in the product description. You can also look them up on the PEGI / ESRB websites.

https://pegi.info/search-pegi

https://www.esrb.org/search/

The already exist on the side bar for rated games. However the majority of games not from those who publish in stores or on consoles don't submit their games for rating, so none exists.

The positioning of the ratings board stuff is usually between the steam deck compatibility and achievements in the side bar.

that is not a steam problem, talk to the publisher of the games that do not already provide this info.

ESRB and PEGI ratings are voluntary. It's up to the game publisher to submit a request to the ratings boards to obtain a rating for their game.

Just picking a random game from the front page of Steam:
https://steamhost.cn/app/3240220/Grand_Theft_Auto_V_Enhanced/

Yep, ESRB rating clearly visible on that page. Always has been.

The thing is, getting an ESRB or PEGI rating costs a lot of money and generally isn't worth it unless legally required.

I'm sorry to waste your time my english is not very good and I meant something else. To be more precise I would like to be able to class my games depending on PEGI and ESRB in my game list. Not by creating my different categories like PEGI 12 or PEGI 7 and add my games manually like I'm doing but rather automatically.
In fact I would like a function in my game list which would allow me to class my games automatically with PEGI rating or even the content like drugs or nudity.
I hope it will be a bit clearer and less useless and redundant.

Originally posted by Usg:

I'm sorry to waste your time my english is not very good and I meant something else. To be more precise I would like to be able to class my games depending on PEGI and ESRB in my game list. Not by creating my different categories like PEGI 12 or PEGI 7 and add my games manually like I'm doing but rather automatically.
In fact I would like a function in my game list which would allow me to class my games automatically with PEGI rating or even the content like drugs or nudity.
I hope it will be a bit clearer and less useless and redundant.

Even with a search by ratings, you would have to be quite careful with games based on content. Disgaea series for example is a pegi 12/ T rated series, but has a lot of sexually charged humor and commentary, while a game like balatro went from 3+ to 18+ to 12 because apparently people can't comprehend a game based on poker.