There are companies that will provide the full package that you're looking for. For example, this company:
https://www.theskigathering.com/ski-holidays/snowboard.php
However, I wouldn't personally go with them myself as they don't offer single rooms. If you're travelling alone then you will have to share with a stranger. That's a definite no for me but if you're OK with that then maybe something to look at
Alternatively, Crystal Ski do two trips per year for beginners where they organise everything, snowboard hire, lift pass, lessons etc all as part of the package.
The only thing is that it is for beginners or, as they put it, "You’ve only taken a few hours of lessons on an indoor slope". Prices this year were £845-1095
https://www.crystalski.co.uk/beginner-ski-holidays/slope-starters/
Then there are other companies that specialise in just snowboarding. For example, I have been with this company, Mint, they're based in Morzine in the French Alps. They do a beginner/improver week long camp which includes everything and five whole days of lessons. This year the prices were €1,600 (£1,400). They do everything, from hiring the snowboard, to getting a lift pass to making sure you know where to go for the lessons etc
https://mintsnowboarding.com/camps/beginners-snowboard-camp-avoriaz/
I can really recommend them, if you have a look at their reviews on Trip Advisor, it's not just me either.
Alternatively, if you google something like "snowboard camp" then that should bring up other companies that do something similar, ie arrange everything for you as a package and handhold.