What does Felony B RSMo 195.211 mean?

"RSMo 195.211" means "Missouri Revised Statutes, chapter 195, section 211".

It has to do with production or distribution of controlled substances (drugs, or possibly ingredients that can be used to make drugs).

"Felony B" refers to what Missouri calls a "class B felony", which is a felony (a severe crime, worse than a misdemeanor). Class B is the second "worst" kind of felony; class A felonies are murder, some kinds of kidnapping, forcible rape of a child, and so on.

The various classes are used to determine what the maximum sentence for the crime is. Class B felonies have a sentencing range of not less than 5 nor more than 15 years in prison. Under certain conditions, repeat offenders can be sentenced for a class B felony as if it were a class A felony instead: 10-30 years, or life imprisonment.