SIM card on iPad Pro 10.5 2017 tablet is not on right side?

There’s no SIM slot on a Wi-Fi only iPad. SIM cards and SIM slots are only present on cellular-capable iPad models.

For those models with cellular support: Remove or switch the SIM card in your iPhone or iPad - Apple Support

What model number is your iPad Pro? You can find out by looking at the back of the tablet and looking for Model Number: -----.

Or you can go into Settings-General-About and look for Model Number. You can tap on it to get a different result which will be easy to identify.

It is possible that you do not have a Wifi+Cellular model which means that you will not be able to insert a SIM card.