There are many websites that provide material for preparation for eamcet as well as provide mock tests.

The websites are:

Carrers360

Tcyonline

iexamonline.com

You can refer to these websites for content, mock tests.

Also, there are many books in the market available for the preparation of eamcet.

Moreover there are many apps that you can refer to.

Hope this helps. Please feel free to ask any other queries.