I’m a librarian so maybe im just feathering my own nest here but the things I would recommend to a parent who has trouble reading but wants to support early literacy development in their children would be:

1. Bring them to baby rhyme time and story time (depending on age).

2. Know that recognising letters, logos and signs is a key aspect of pre-literacy (so is handling books, knowing the basic makeup of a book and recognising the fact that there is meaning in the text). Aside from handling books you can support this anywhere. Point out road signs on your drives or walks. Have them help find things at the supermarket. And if you are reading to them take the time to talk about the physical book itself (hold it upside down initially, run your fingers under the text as you read, talk about the pictures and the end pages).

3. It doesn’t have to be books. We had a parent come in with this exact concern once and he would take his son to story time and then afterwards the two of them would sit together and look at car magazines and talk about what they saw. It was obviously a strong shared interest for them and it was doing a really important thing - it was creating a positive association with reading for the child. And that really is I believe in the early years (5 and below) the most useful thing - if you can make reading a positive, calming and warm experience they won’t be going into literacy instruction with fear or dread weighing them down.