DK (Double knit) yarn and a number 4 hook is all you need to get started. Depending on the hook you buy it will cost less than £5 to get started.
I learnt from the Attic 24 blog, her mixture of written pattern (yes, patterns look like a foreign language to start with) and photos were really helpful. If you can learn a slip stitch and a triple crochet you can make al sorts of blankets on her site. There are helpful Facebook groups too.
Bella coco's video tutorials are also brilliant and I often use them to refresh my memory before trying a stitch.
Coastal crochet stash buster looks very daunting but her mix of written pattern, photos and videos make it appropriate for a beginner.
In my experience my Dd loves handmade blankets and ponchos and doesn't care if there are mistakes, in fact she likes to try and find them like 'Where's Wally' . Mistakes are what give handmade items there charm.
In January, Lucy from Attic 24 is doing a crochet-a-long (CAL) where a few rows are released each week, this would be a great time to start. Get the yarn pack from Woolwarehouse when it's released next week its called Meadow and there will be lots of support available on Attic 24 Facebook groups as people complete it together.