1st offense marijuana possession is an offense that the court can dismiss after a period of successful probation. A 1st offense possession with intent to distribute, distribution, manufacturing, etc, pursuant to 18.2-248 will likely carry an active term of incarceration. A skilled defense attorney may be able to have the felony distribution offense reduced to felony possession, which may then trigger probation, no incarceration.
I am unable to fully answer your questions without more facts, as the facts in these types of situtations help determine what the likely outcome will be. The crimes you are inquiring about are respectively a misdemeanor and a felony, for which the jail times are (respectively) 30 days maximum, and 1-10 years maximum.
As you can see from above, the second charge is a very serious charge, and your friend should consider consulting and retaining an attorney to assist her in this matter.
Disclaimer: This response was prepared for information purposes only, and should not be construed as legal advice nor does the information imply any guarantee as to the results of future litigation. You should not act or rely upon this information without seeking formal professional counsel specific about your case.