Then this chart for comparing:

There are distinct differences: fibromyalgia is this:

No, these are two different diagnoses.
Fibromyalgia definitely includes chronic fatigue.
But, many health conditions also include chronic fatigue.
However, M.E./CFS is a separate diagnosis.
From the NHS:
Myalgic encephalomyelitis, also called chronic fatigue syndrome or ME/CFS, is a long-term condition that can affect different parts of the body. The most common symptom is extreme tiredness. The cause of ME/CFS is unknown.

ME/CFS can affect anyone, including children.

Symptoms of ME/CFS

The 4 main symptoms of ME/CFS are:

feeling extremely tired all the time (fatigue), which can make daily activities like taking a shower, or going to work or school, difficult
sleep problems, including insomnia, sleeping too much, feeling like you have not slept properly and feeling exhausted or stiff when you wake up
problems with thinking, concentration and memory (brain fog)
symptoms getting worse after physical or mental activity, and possibly taking weeks to get better (also called post-exertional malaise, or PEM)
Some people with ME/CFS may also have pain in different parts of the body or flu-like symptoms, such as high temperature, headache and aching joints or muscles.

The symptoms of ME/CFS are similar to the symptoms of some other illnesses, so it’s important to see a GP to get a correct diagnosis.

Myalgic Encephalitis:

But keep in mind that chronic fatigue is a symptom that many conditions have. For example: fibromyalgia. Anemia. etc etc
ME/CFS also sometimes referred to as chronic fatigue syndrome is a separate condition.
Hope that helps :)