I have no clue what is wrong but it started to putter on the highway but it still would go as long as i stayed at a certain speed, the speed varied to it would let me go 45 sometimes and 65 others. When i got to my friends house it would not start at all and when i tried to flood it to start it, blue smoke rolled out so i figured it was the 02 sensor. Well i changed that yesterday and still it doesn't start. Anybody have a clue?

 

It could be a ton of different things that fit that description and behavior.
Can you give more information about the car to help narrow down the possibilities.

What year car?
What size engine? V6,V8, 350, 305 etc.
What type of fuel system, Carb, TBI,. TPI?
How many miles on the engine?
Have you changed anything recently?
Heck, even what was the weather like that day?

The more information, the more we might be able to narrow down the possibilities.

 

It is a 1990 Camaro IROC-Z with 305 5.0 L... TPI with 62000 miles on the engine. Just changed the 02 sensor and tuned it up not to long back.. prolly 3 months ago. It was a nice sunny day.

 

O2 sensor won't affect starting. Pull your trouble codes, there's a tech article on this site. Behavior like that should have tripped something.

Resist the urge to plug in new parts/pieces at random. Start with the basics: fuel, air, spark.