Books are always good. Realistically they don’t need much in the way of toys at this age. Sensory toys, rattles etc might be good. Maybe a projector or a bubble machine?
For my older sons first birthday we asked everyone to buy him their favourite childhood book and put a message in the front - he has a lovely library now.
Sensory items/ interactive toys/ bigger sized clothes x
I used the early learning centre website. They go by age and have loads on x
There is sensory balls in Argos. Lovevery does very great boxes with toys according to the age. Also something with music they will like 🥰