How to approach doctors?

Me and my fiance have been ttc on and off for a year and we've decided we need to go to the doctors to see if there are any underlying problems. Silly as it seems I don't know how to approach it, do I litually just walk into the app and say we've been trying for a year and nothings happened could we have some investigations? Is it covered on the nhs? Also do we have to be with the same surgery to have both of us explored? Many thanks