See the Speech and Language resources below to support language and understanding of both expressive and receptive language.
Try the free app Bitsboard.
Have a look at the resources on: https://www.speechandlanguagekids.com/free-materials/
This is to support language production.
Colourful Semantics have a banks of resources for free to support early language and sentence construction: https://integratedtreatmentservices.co.uk/our-approaches/speech-therapyapproaches/colourful-semantics-2/
The Communication Trust links to different resources for parents as well as schools (some free) as well as offering some free training which is very interesting: https://www.thecommunicationtrust.org.uk/