The measurements you say is confusing, so here is abit of help

Alot of injectables will be addressed as this:

250mg/ml 10ml vial.
This means there is 250mg of steroid per ml and the vial consists of 10ml.

So when injecting if you are injecting 250mg of Test E for example you draw the syringe to the one ml point, as this would be 250mg

Hope this helps abit.

I suggest you put off even consider using steroids until you know everything that you have to do when using gear. Learn aboutside effects, anti estrogens, pct, different cycles, injectables vs orals, and etc, alot to learn.

Most beginners try a simple cycle which includes:

Testosterone enanthate or Cyp

Both of these steroids are injectables and the most favouredfor beginners. Why? Because they are the injectables that need to br used only once a week where as other injectables might need to be used every other day.

So basically a cycle is run with the Testosterone as the BASE if the cycle, then people dress this cycle with other products such as Dbol which is an oral steroid, but i recommend you only use a injectable steroid for your first cycle. Why? So you can easily monitor your bodies reaction to this drug, then add other products in later cycles.

So now you have your basic steroid set you now nees to know how to ise it. So test E (yest enanthate) has a half life of 10 days so you need to inject this atleast as a bare minimum every 10 daya but most peoplw do it every 5 days to keep their testosterone levels norw consistant, which is highly recommended. So inject 250mg of test E every 5 days, this is the MOST effective way of injecting Test E. Test cyp (cypianate) is very similar to Test E so use it as you would Test E. the inly difference in the two is Test Cyp has a slightly longer half life.
You keep doing this for 12 weeks and that would be your first steroid cycle complete, alot of pwople gain around 15lbs in this type of cycle so the gains are great.

So now your steroid cycle is over, it's time to begin the most important part of using safely. This is called PCT (Post Cycle Therapy) this involves using multiple products all aimed at reducing your estrogen levels back to normal and restoring your testosterone back to normal. This PCT will begin after the steroid has cleared feom your body. So because Test E has a half life of 10 days, you will begin using PCT after 20 days.

There are many types of PCT products all aimed at reducing estrogen and products for increasing testosterone. The most popular products include Clomid Nolvadex and Aromasin, these three products are uses for reducing estrogwn and a three are used in combination with each other, commonly in these doses:

Clomid 100mg everyday for week 1 & 2
50mg everyday for week 3 & 4

Nolvadex 20mg everyday fir week 1&2
10mg wveryday for week 3&4

Aromasin 12.5mg everyday for week1&2
6.5mg everyday for week 3&4

So PCT should be run for 4weeks and started 20 days after your last injection of Test E or Cyp.

There are lots of other ateroids and anti estrogens and Peptites etc but these are the basics which i would recommend for a beginner.

I also highly recommend you to so your own research, eroids is a great place to find all thw information you need.

Hope this helped, thanks for reading