What does a new air compressor need before adding frion

Did you read the FSM yet or at alldata.com yet,then ask about steps
there that are confusing, or ??? any thing?
air? what air?
the steps for A/C HVAC are all the same.
1: capture the old Freon (liquid gold) or go to jail. (USA)
2: run cleaner through system, to get the debris from death of old compressor out, (if the expansion valve is packed it's hopeless)
3: back together. now. with new receiver dryer.
4: pump it down with the vacuum pump, this removes all moisture , that kills Freon(tm) Dead. A/C loop hates water, in any form.
5: Add the R134 oil. (new unisiveral type)
6: add the freon by weight, do not overfill. FSM tells this,,,, read it.
7; Run it and adjust freon amounts, per the tables in the FSM.
The table shows 2 things, (input) air temp, and humidity, then adjust
pressure per chart.
8: using a vent thermometer check that the system really is at spec.

(i do the elect side, the above, is the loop side. and above is SHORT LIST)

Read the directions, in most cases you need to drain the shipping oil in the compressor the refill with the proper type and amount. Go to a reputable parts store in your area and they should supply you with the proper stuff