To be in a fix simply means to be in a confusing or frustrating situation.
To be in a dilemma

The act of preparing a drug for use instravenously.

“Fix on” is a phrase mingi from ateez, a kpop boy group, usually uses right before his rap part

Generally used only in the state of Texas, 'fixing to' is the equivalent of 'about to' or 'getting ready to'. If used outside of Texas, likely the person using it is from Texas or has spent a great deal of time in Texas. Also, this person will likely be on the receiving end of, "You're... what?"

A date. A lover. Someone you can share free love with.

used to indicate the act of beating someone up.

All Setup For Something And Nothing Can Change Your Mind About It.