How many cell layers compose the lower epidermis?

There are 5 layers in the epidermis and I think you are talking about the dermis (dermal) which is 2 layers thick.
The epidermis is composed of the 5 layers as
1- stratum germinativum,
2-stratum spinosum,
3-stratum granulosum,
4-stratum lucidum,
5- stratum corneum.