To be selected as a federal skilled worker, you need a minimum skill level of at least Canadian Language Benchmark (CLB) 7 in each of the four abilities (speaking, listening, reading, and writing). You must meet the threshold in all four abilities or your Express Entry profile will not be considered under the Federal Skilled Worker program.
In the case that you have a proven medical disability preventing you from being able to obtain a score in one or more of the four skill areas, you are required to include the average score based on your assessed abilities. Use the Comprehensive Ranking System – Language tool to find out on how to do this.