In order to edit OFP you need tools and utilities. Main categories are as following. Islands: WrpTool. Models: Oxygen 2 Light (O2). Textures: TexView. PBOs: PboX. Optimizing models: Binarize.

Binarize

Oxygen 2

Oxygen Viewer / Buldozer

TexView

Pal2PacE

Visitor 2

Wave2lip

BinView by CoC

CfgCheck by vektorboson

GateBuilder by bxbx

ODOL Explorer by PMC

obj2p3d by Fliper

P3DEdit by OFPInternals

P3D Texture Swap Utility by Mike Schell

p3d2obj by a-lone-wolf

PaaTool by feersum.endjinn

PatchPbo by Mikero

PAnTool by Dschulle

PboX by PMC

TxtPathSwap by feersum.endjinn(?)

Wilbur by Joseph Slayton

WrpEdit by OFPInternals

WrpTool by PMC

wssfileconverter by Stoppelhopser

xPack by a-lone-wolf

Binarize, Oxygen2, TexView and Visitor 2 check Bohemia Interactive breathe page.

Command Reference download from BIS page.

Briefings by BIS download from BIS page.

TexView v1.1 to edit textures download from BIS page.

BIS sample models in MLOD format download from bis page.