"Barron's AP Physics C (2020) 5th Edition" by Pelcovits and Farkas
Chapter 11 - Coulomb's Law and Electric Fields Due to Point Charges
Read pages 320 - 326
(Start at "Potential and Voltage")
(Stop at end of chapter)
Chapter 12 - Calculating Electric Fields and Potentials Due to Continuous Charge Distributions
Read pages 497 - 505
(Start at beginning of chapter)
(Stop before "Calculating the Electric Field Due to a Continuous Charge Density: A General Approach")