I would find different products from different brands as I don't think one brand does everything really well.
My mum likes brands like Guerlain, YSL, Clinique, Laura Mercier, Chanel, Estee Lauder and Dior.
I'd suggest to go for a tubing mascara (loads of brands have them - Clinique, Estee Lauder, L'Oreal and so on) as they don't smudge in the same way as normal mascaras - my mum struggles with that a lot.
Foundation - something with as sheer/light coverage as possible. My mum likes Guerlain foundations, but they are quite dark, so Estee Lauder or Laura Mercier might be better (and cheaper). I'd suggest to get samples of foundations before buying.
For lipsticks, my mum usually goes for Chanel, Guerlain, Dior or Clinique. I gave her some Chubby Sticks a while back and she loves them.
I'm not sure which blushers my mum use, but I really rate Mac - but most brands have good blushers.
She likes using Guerlain Meteorites all over the face.
I don't think my mum uses concealer, but I'd recommend Laura Mercier Secret Camouflage.
For eye shadows, she usually goes for Dior or YSL palettes, but I've noticed that they crease on her and she doesn't want to bother with primers and so on. So if your mum might have the same issue I'd suggest a cream shadow such as Chanel Illusion d'ombre or Laura Mercier Caviar Stick Eye Colour (and a Mac 217 or similar to blend it out with). Loads of other brands make cream shadows that set and stay put all day - Mac have their Paint Pots, Bobbi Brown have some eye shadow sticks too.
For eyeliner, I'd suggest a dark powder eye shadow or gel liner and a Mac 212 (or similar) brush to push the colour into the roots of the eyelashes - it's easier if not used to applying liner and if you can't see much without glasses
and it's very natural - it just makes the lashes look full and really good.
Wayne Goss did a video about it:
I'd also suggest to get an eyebrow product of some kind as the lashes seem to get more sparse as we age and the thinner brows can age us a lot. I like using a powder with an angled brush and then brush through with a spoolie.