Do they float iniside our "blood blob inside our body" or they are connected to our muscles ?
They’re fastened together by blood vessels, nerves and most importantly, connective tissue, muscles and bones.
Image Source: anatomyorgan.com
Image Source: Britannica
The same holds true for other organs in the body, although the skin and the brain are slightly different cases.
The brain does float around, albeit in the cerebrospinal fluid, and very rapid movements (like hitting the head) can cause the brain to clash against the skull, causing a concussion.
Image Source: Wikipedia
The skin is a muscle itself, connected to other muscles and tendons and is also supported by the skeleton.