Welcome!
Where you are in the world affects your service options, and we don't know where you are.
In the US at least, Apple have a "Send in for repair" service where you drop off the device at a shipping company's storefront shop (like the UPS Store). I am not sure whether warranty service is the same as out-of-warranty service but I believe they are.
When I used that service for an iPad battery service out of warranty, I dropped off the defective iPad at a UPS storefront locations on a Friday morning and had the replacement in delivered to the house by noon Wednesday. If you are not in the US, you may not have this option, so start here to see what options you have:
iPad Repair and Service - Apple Support
To minimize turnaround, Apple U.S. does not repair most devices but sends you a fully refurbished device of the exact model and identical options as the one you sent. My replacement was perfect in every way and is still in service. Refurbished units get a thorough testing plus a new battery and new outer shell.
Personalization:
— if your original was personalized by Apple: they will re-engrave your replacement with the same inscription. When I had my iPad serviced, information provided by Apple said they do not charge extra for this but that it adds 3-5 days to the total time for replacement.
— if your original was personalized by someone else: you are on your own.
If you take your iPad to an Apple store, they are going to ship if off to the same repair/refurb facility. That wil add about a day at each end to your "time without iPad." "Send I’m" is a great option if available.
