Make sure you use sunscreen with your retin-a if you're being exposed to sunlight.
I would use a really good moisturizer you feel is suited well to your skin. I use sunday riley tidal brightening water cream and I LOVE it, but its pricey. I use it at night but have used during day.
What I would recommend trying is this cream instead(more like a gel). Currently I am trying out first aid beauty coconut water cream. I currently use it during the day with other skin care (sunday riley good genes, drunk elephant vit c serum mixed with drunk elephant b hydra and THEN the water cream) The cream itself, I really like how much moisture in it. Its hypoallergenic and should be perfect on sensitive skin. Its not heavy, its gel and light weight, dries in a way that your skin feels soft. (Thanks to the dimethicones, which are not a great ingredient for skin care- watch for breakouts). The skin also sucks the cream in immediately and the price is pretty good.. The product states that it is hypoallergenic, non-comediogenic and suitable for sensitive skin. Looking at the ingredient list like I kind of mentioned before, there are some suspect ingredients that I would be skeptical about (in the way they might break out your skin) However, their study says all their participants didn't break out at all. So far so good for me, but its a new product.
I buy the drunk elephant b hydra , by itself its not an exciting product, but it has ceramide which helps maintain skin barrier, hold in water etc. Its like a supercharge to a good moisturizer. If you look at the photos that are under the product on the website, everyone's skin is GOALS. Youthful, clear and soft. Seriously, go look.
But if I see dryness and flakiness that isn't from your skin getting raw(say like you would in acne treatment), I would make sure you're removing your makeup adequately, washing adequately and exfoliating adequately. Chemical exfoliants are the best, as the grit ones tear your skin up. I use sunday riley good genes(lactic acid treatment) and it clears my skin up because its decongesting my pores, works deep and is responsible for notably cleaning up my acne with the luna(which has retinol).. There is an instant and noticeable difference with good genes. Along with all the other things it does I consider it a miracle ?treatment ?serum, ?cream, ?unicorn dust. Whatever it is called, it basically got me pretty enthusiastic about good skin care. If you are using retin-A and you ever decide to try the good genes, I would be very cautious about introducing it, you might have to alternate days etc. It is extremely pricey and since you're worried more about getting a moisturizer I don't expect you to get it, I'm just giving you overall advice if you ever decide to use it.
I also now use the fareo luna tool and it gets my skin clean like no other. Its gentle unless you have open spots on your face, otherwise it basically polishes any trace of makeup, dead skin, EVERYTHING off your face. So I have no dry flakey skin on after that which will happen if I don't get my skin clean enough. I also don't have any deep seated makeup that sits in my pores. If you didn't want to spend the money on that I would use a similar, cheaper, non vibrating silicone pad/scrubber. Wash cloths are too harsh, unhygienic and don't get the job done right in my opinion- which has lead to flaking and buildup in my experience. Washing with your hands just does not get it clean, leading to the same. Those spin brushes are also unhygienic and harsh but they clean your face well.
Lastly you need to check if you are using the right cleanser. Like if I used dove soap on my face that would happen because it strips my skin and dries it out. I have combination skin and I'm still trying to find a new cleanser since my glamglow duo cleanse(oil and clay/mud) cleanser was discontinued. Just started to test the drunk elephant jelly cleanser only at night, once a day.
I'm not super knowledgeable about skin care, but this is what my skin care routine has worked itself up to at the present time. I think its important to look at all the steps you are doing to make sure something like dry skin isn't being caused by a mistake in your routine(eg poor exfoliation/cleansing). Sephora is great because often you can get a trial sized sets that you can test and introducing into your routine without buying the whole product. Its been a way I've built up to my current anti-aging/improving texture/scarring/blemish clearing routine I have going on. I'm 25 so I'm hopeful that in particular my anti-aging routine (besides the instant benefits I get now) will pay off when I turn 40 and 50. 🙂
I know its a lot of extra information, but hopefully it gets you thinking about the whole picture.