you need to start with the basics- first, is the clutch free, sit in and depress the clutch and see if you can engage any gear, or see if you can find neutral. If you find neutral, fine. Next the engine, is it free. Remove all plugs and put spanner on the starting handle nut and try turning it. If turning, fine. Go to Halfords and buy a compression tester, contact jeep parts sellers and buy a starting handle, makes life much easier for cranking round the engine.
If it was my Jeep and it had been standing for a long time then the only correct way to recommision it would be to remove engine , strip it and check all the innards. Its no good worring about fuel lines, electrics or anything else at the beginning. If you need to clarify anything contact me. John.