It sounds like you already have the essentials down so adding Retinol is definitely the next step to take!
So I started using Retinol first and then gradually built up to Tretinoin (prescription-strength Retinoid).
I used The Ordinary’s Retinol which is really affordable and easy to find from Boots or other beauty websites.
For prescription strength Retinoid, I use Dermatica - its a monthly subscription service and (as far as I know) the easiest way to buy Tretinoin in the UK. There’s also Skin+Me who offer the same service, I think both do free trials so you can try each company before committing!
When you use Retinol/Retinoids, your skin will become more sensitive to the sun and will likely become irritated (drying and peeling is very common!) so it’s really important to wear SPF and reapply during the day. I started using Tretinoin just a small amount twice a week, then every other night, before using it every night.
This is my routine (I find less is more when it comes to skincare, but everyone is different!)
AM:
Wash face with water
Moisturiser
SPF50 (reapply midday)
PM:
Cleanse (using a gentle cleanser without any actives/acids like glycolic or salicylic acid)
Tretinoin/Retinol
Moisturiser (you can also moisturise before applying Retinol to help avoid irritation, especially when you first start!)
I’m not an expert and it can be trial and error to find what works best for you, but hopefully this helps a little bit