My mom tends to play Civilization 5 and Final Fantasy XIV a lot.

Try sims 4, atleast play it yourself so you know what you are doing, even when in game has plenty of guides.

I mean what are the odds for find a 3D shooter mom, sure they are there, but they are rare. imo.

Plenty of games with adventure if that is more her things.

For while, many PC games were targeted toward teen and young adult males. It wasn't noticeable in the early days. Arcade games like Space Invaders and Pac Man were pretty universal. But I remember a pretty hard shift sometime in the mid-80s toward my demographic -- teen males. A lot of box art suddenly had half-naked elf women in chain mail bikinis, and advertisements eventually promised to make you the game designer's ♥♥♥♥♥. So, if she's from that era, it's probably coded in her mind that PC games are for teen boys.

My younger sister is a 50 year old mom, and she plays some of the same games as me, though.

My mum loves ghost n’ goblins 💀

Try FTP
https://psteamproxy.yuanyoumao.com/genre/Free%20to%20Play

its not about the games its about so she learn other games she want, like management or platform games, to site here and say carmen sandiego or monkey island from the past even lucasart games games, list is so long.

And you can also investigating other steam users open profile for inspirations, typical other steam user you have same game also might have other semi same likes. in whatever forum game she also have current games.

Check this

https://psteamproxy.yuanyoumao.com/app/29180/Osmos/

https://psteamproxy.yuanyoumao.com/app/3590/Plants_vs_Zombies_GOTY_Edition/

My Mum like the sims games alot.