Welcome to the forum. On older Autos like my Clio there is a distick for the ATF. However on the newer models there is not and the Haynes manual states that special measuring tools are needed and to take to Renault. Although I would guess an independent or auto specialist will also have the necessary tools.
Hi i drive 2002 2.0L 16v espace with a auto gear box i do know that your gear box takes 6L but when you take the bottom plug out of the gear box only 3.5L will come out and 3.5L will remain in the top torque converter and pump so you only have to put 3.5L back in when doing this.
But to check your Auto oil level there might be another plug halfway down the side of the gear box and if this plug is took out and oil runs out your level is ok if not you are low and will need topped up or even changed but not all gear boxes have this so you may have to go to the dealer to have it checked..
The oil in the auto gear box should be replaced every 36k and can only be got from them and the oil is elf RMATIC D3 FULLY SYNTHETIC i hope this helps you cheers