how to reset engine after repairs?

[03MstyleX5]

first off ive searched high and low on the site. over the weekend i did some pretty intense ripping apart of the engine on my m62. i replaced the valley pan which wasnt an easy task. also the valve cover gaskets and a bag full of other gaskets along with everything else. this morning when i completed everything when i went to start it it turns over but then it doesnt idle and stalls right away. if i push the pedal it revs up but then stalls immediatly. im thinking something needs to be reset considering the amount of wires and sensors that were pulled off. is this a possibility or does it sound like a sensor or vacuum hose isnt connected properly. im 100% confident in how i put everything back together so im very confused. if anyone has an idea of what my problem could be id appreciate it.