I hope this is on the right track:

Postal service standard suffix abbreviations

Finish of bronze or finish of gold.

Bronze is 3rd → RD (road) and gold is 1st → ST (street)

Uncurse my bluff and the way will be told.

bluff - fu → BLF (bluff) and WAY (way)

In fiction and fact, at the edge of the grave.

In fiction and fact → CT (court) and edge of grave → AVE (avenue)

I'll fit in a tux if I see where you pave.

Guessing here: a tux is a jacket with jct fit inside giving JCT (junction) and then AVE

I'm a dragon's start — a circus split up.

dragon's start → DR (drive) and circus split → CIR (circle)

I'm a term's first part — to pass, sum it up!

term's first part → TER (terrace) and PASS (pass)

Title: Confused… why?

HWY (highway)

I hope this is on the right track:

Postal service standard suffix abbreviations

Finish of bronze or finish of gold.

Bronze is 3rd → RD (road) and gold is 1st → ST (street)

Uncurse my bluff and the way will be told.

bluff - fu → BLF (bluff) and WAY (way)

In fiction and fact, at the edge of the grave.

In fiction and fact → CT (court) and edge of grave → AVE (avenue)

I'll fit in a tux if I see where you pave.

OP addressed: if I see where you pave implies view → VW (view) fits nicely in tux (tuVWx)

original try: a tux is a jacket with jct fit inside giving JCT (junction)

I'm a dragon's start — a circus split up.

dragon's start → DR (drive) and circus split → CIR (circle)

I'm a term's first part — to pass, sum it up!

term's first part → TER (terrace) and PASS (pass) and, from OP, sum it → SMT (summit)

Title: Confused… why?

HWY (highway)

I hope I can address this correctly by posting that this contains

Postal service standard suffix abbreviations

Finish of bronze or finish of gold.

Bronze is 3rd → RD (road) and gold is 1st → ST (street)

Uncurse my bluff and the way will be told.

bluff - fu → BLF (bluff) and WAY (way)

In fiction and fact, at the edge of the grave.

In fiction and fact → CT (court) and edge of grave → AVE (avenue)

I'll fit in a tux if I see where you pave.

I'm lost here

I'm a dragon's start — a circus split up.

dragon's start → DR (drive) and circus split → CIR (circle)

I'm a term's first part — to pass, sum it up!

term's first part → TER (terrace) and PASS (pass)

Title: Confused… why?

HWY (highway)

I hope this is on the right track:

Postal service standard suffix abbreviations

Finish of bronze or finish of gold.

Bronze is 3rd → RD (road) and gold is 1st → ST (street)

Uncurse my bluff and the way will be told.

bluff - fu → BLF (bluff) and WAY (way)

In fiction and fact, at the edge of the grave.

In fiction and fact → CT (court) and edge of grave → AVE (avenue)

I'll fit in a tux if I see where you pave.

Guessing here: a tux is a jacket with jct fit inside giving JCT (junction) and then AVE

I'm a dragon's start — a circus split up.

dragon's start → DR (drive) and circus split → CIR (circle)

I'm a term's first part — to pass, sum it up!

term's first part → TER (terrace) and PASS (pass)

Title: Confused… why?

HWY (highway)