hello, still new to companies. When with a company do you have skills you need to work on? How often would you get trained when working with a company?
Typically any education that is gonna boost your Primary and Secondary Stats in your position; though anything is good at your level. Trains are typically negotiated before you take a job and differ from Director to Director.
Alternatively putting merits into Employee Effectiveness gives huge boost; if you choose to go that route.
You are best served by working at public jobs to earn the perks from promoting to the top spot in each job. I would specifically recommend getting a job in education as soon as possible so that you can get to the principal's job. the perk for getting to that job is a discount in time for all education courses you take after getting to that job.
if you stick with public jobs you can earn perks like the ability to revive (Medical), gain extra crime experience (law), and be able to spy (army), and others that I can't think of off the top of my head. all the time you are in the public sector you are also increasing your work stats which makes you a more desirable employee once you do transition to the public sector.
You can't really work on skills so much but if you take education courses, they increase your work stats which helps improve your overall effectiveness. you can also use merits to give your effectiveness a boost or to help you manage your addiction if you take drugs. that also helps your employee effectiveness.
What I would advice for someone with lower battlestats is joining a company where you get paid with one train per day. That is going to net you a good increase in workstats along your torn career. So, if you haven't already, ask if your director can pay you in terms of trains, preff 1 per day.
I see you joined a clothing store. That's good, since you get +100 endurance per 10 job points. That is going to help you out a lot too.