Hello,
My daughter (3.5) has had eczema since she was around 4 weeks old.
Finding the right emollient/moisturiser is a bit of trial and error and if you're under the care of GP and progress to special interest GP or dermatology consultant they will have their own views on what works, plus there are first line treatments (usually the cheaper ones).
We went through E45, aveeno, Diprobase, cetraben (cream and emollient), hydromol, 50:50, and now are on AproDerm. It's a bit of a mine field as everyones skin reacts differently.
Likewise, other required treatments, such as steroids and immunosuppressants will be dependent on how the eczema progresses. Lots of children will have mild symptoms that get better with just keeping the skin moisturised - and I'd recommend doing this throughout the day, every nappy change, before eating food, after any wiping them down etc, the more often the better especially in winter.
Some people are able to find triggers, such as allergens including foods, but you might not always be able to figure out triggers.
I'd recommend looking at washing powder you use, not using any fabric softeners or perfumed things. Clothing can be an irritant so using natural fibres like cotton, silk or bamboo is recommended for skin. You can get some types of clothing on prescription too but it's either skinnies or comfifast garments (those are the only ones I'm aware of as that's what we've had before).
One thing that massively helped me was the eos.org.uk/ website and support group they have on Facebook. I'd really recommend looking at joining as there are parents from all over who offer advice and speak about their own children's eczema.
Scratchsleeves and cotton comfort clothing both do special PJ's where hands are away (for those scratching times) and other products that are useful.
Sorry for such a long post! Hope things go okay for you.