Hey welcome to curly life!
A lot will come on here to suggest the curly girl method, but it's a hell of a faff (though do look into it, you may like to try it, but I found it too much faff).
I use shampoo and conditioner for curly hair (currently on John Frieda, but move around depending if there's offers on).
I wash with the shampoo, then condition, and comb my hair with a wide tooth comb (my hairs also super thick) when the conditioner is on, then I don't comb it again!!
When I get out, I use a T-shirt to scrunch the dampness out the hair. Then I use a curl forming serum (again currently John Frieda but I do love frizz ease) and scrunch that in.
Then in"plop" my hair, meaning I lay another T-shirt on a bed, bend my head forward til all the hair is dangled into the T-shirt then wrap it around my head and secure. I sleep in it usually. Take it out in the morning to lovely smooth (mostly) curls.
Other times I leave it for an hour or two if I wash it in the morning.
The main things are: good conditioner, don't brush or comb once dry, good frizz ease or curl serum, don't use a towel to dry as it's too rough. I also only wash it once or twice a week.
I don't find diffusing helps my hair - just frizzes up. But I've read good things about remmington.
Have a search on your tube for curly hair technique or diffusing there's loads of good tutorials