I have found that YouTube is a great resource for that. Just search tutorials for the CAD platform you are looking for. You can narrow your searches based on specific techniques (i.e. 2D CAD, 3D modeling, assemblies, drawings).

there is a collection of books "mechanisms in modern technology" authored by Artobolevsky. 7 volumes of various mechanisms. if you find it in your native language, you will be provided with tasks for several years.

This tutorial has received fantastic feedback: https://www.jig.space/tutorials/jigspace-3d-model-preparation ... Let me know if it helps!

Another free program is by Udemy