Working stats

How do I increase my Working Stats and what stats do I need to join a Company? I currently have Manual labor 3, Intelligence 1 and Endurance 2. 

To increase your stats, keep grinding.

To join a company, easiest way is to reach out to owner and ask for a job directly. You may get a bunch of no, but you only need one yes.

working stats are increased just by having a job, different stats are increased more or less depending on the job, and you can also get trains from the director of the company that increase your stats even more. As for what stats you need to join a company, It depends on what company youll be joining and the amount of stars it has, lower stars are more likely to hire lower stats.

education also give a very small boost on work stats.

Dude, I took a look at your profile.
You're level 3,.204 days old That already shows you're not active in the game, which alone makes it difficult for any company to hire you.
Now, if you've decided to actually play Torn (actively) daily, since you're a low level and your attributes are also low,

I advise you to create a new account and be active, okay?

Not everyone plays Torn the same way. Some people are barely active, some are always here. Yes it is true that it may be harder to find a job if you're inactive, same with a faction. But that doesn't mean that the account is worthless; there's no real reason to restart, just start being more active and catching up if that is what they want. Lots of people come and go, and you just pick up where you left off.

Given your stats are a little low at the moment you could join one of the entry level city jobs, your other option (if you have the cash) is to buy trains.  

You are 71 days, in a trap faction and started a flower shop.  How to be effective is not your cup of tea.

Unless someone completely destroyed their reputation there is no need to restart.  Everything can be fixed with the only other exception of unfixable being rehab bills from using drugs in a crap faction without the perks.

Fastest way to get work stats is to buy training in a player company, but it's not that cheap when you're new.   Some companies will hire you,  look for rotating training to save money.   Look for companies that have perks that mostly appeal to new players.   Their more likely to accept your low stats because people with higher stats don't want to work there.  

I made my account a long time ago but really started playing a few days ago. I made it to save my name and kinda forgot about it until I saw an ad for this game again.

Start with the city jobs, Education first, when you don't have the job points to get a promotion spend them on working stat growth. Use education to get the stats required to max out Law as well. After that you can do medical if you want to have the option to revive, but thats optional.

Then you read a guide on getting the affronted merit and your all set to move onto player ran companies with a nice pool of stats behind you! :)