1.
If you fix something up, you arrange it.
I fixed up an appointment to see her...
PHRASAL VERB: V P n (not pron), also V n P
2.
If you fix something up, you do work that is necessary in order to make it more suitable or attractive.
I’ve fixed up Matthew’s old room...
= do up
PHRASAL VERB: V P n (not pron), also V n P
3.
If you fix someone up with something they need, you provide it for them.
He was fixed up with a job.
PHRASAL VERB: V n P with n, also V n P