For what it’s worth (please don’t criticise me

):
Clothing - Myself and a few hunters I know swear by Deerhunter clothing (Muflon Light trousers and jacket) - New Forest Clothing stock the full range plus their own brand stuff looks good too, haven’t tried but will soon. They currently have a 10% sale on.
The Deerhunter clothing is expensive (but still cheaper than Harkila). Buy whatever you like the look of and that feels comfortable but make sure it’s warm, waterproof and silent.
Personally the cut and fitting of the cheaper brands didn’t suit me, such as decathlon or Jack Pyke but if it works for you then great.
Consider a base layer and hunting socks (sealskinz are good)
You’ll need good boots or wellies and decent hat and gloves.
Other miscellaneous kit:
First aid kit
Knife (More Companion or Double Edge
Swingblade)
Thermal - for spotting heat source (misconception that these are only used in nighttime is incorrect as they’re used during the day too and they’re mega expensive). Pulsar is a good brand but there’s HikMicro too
Bino’s - you’ve said you already have - these will be useful for identifying the deer species (esp after using thermal to find the deer)
Shooting stick (I prefer quad sticks) - Personal preference here but ViperFlex are good however there’s a user here selling 3D printed carbon Fibre kits which you DIY (these are awesome)
Free: - GMM 3D Printed Quad Sticks - Assembly Instructions
Deer Sack - You might want to consider buying a deer sack depending on how accessible the land is where you’ll be shooting and whether you can get the vehicle close enough to collect the deer.
Google Phil Ogden Shooting Supplies, he’s a very nice guy and his gear is quality - very highly regarded. Some of his gear is also white-labelled by Monarch so check out their website too.
I’m a novice hunter myself so don’t take any of the above as gospel. One thing to note is that the more people you ask, the more opinions you’ll get so buy what you like and what fits you and your budget. Be prepared to go broke - it’s called the Royal sport for a reason
Sign up to the DSC1 course, not only will it help educate you but it seems to be a requirement when getting permission to shoot on land or joining a syndicate.
Don’t forget the beard - it’s compulsory
Good luck and happy hunting.