New to gardening

Hi & welcome Tom, hope you enjoy the forum. I haven't downloaded your plan as I'm always wary of downloading PDFs if I don't know exactly who they're from, maybe you could also attach a photo of your sketch (via the 'add image to post' button at the top right) in case other members are cautious as well. Hope you & Sophie have fun planting up your new garden & settling into your new home. Whereabouts are you, I'm assuming U.K. but our advice would be different depending on your location.
I'd suggest that if you check things like which way your garden faces & where the sun shines on it & for how many hours a day etc. & maybe get a cheap soil tester to see if your soil is acid or alkaline to give you an idea of what will grow in your garden. Normally I'd say look at what is growing well in neighbours gardens but as it's a new build they're probably all in the same boat.
For year round colour I'd plant a mix of shrubs, bulbs, perennials & add annuals for a burst of colour in summer. You can start planting bulbs between now & the end of the year for spring colour once you've prepared your flower bed which will probably need some compost etc. adding to it & just mark where you've planted them with sticks etc. so that you don't dig them up by mistake.

Tom we all had to start once. My first was a grass area for the cats about 3sq ft in Mums small garden about 75 years ago.

My advice would be, join a local garden club, hunt every garden shop in your area, ask plenty of questions and start taking notes of what is growing in your local area. This Forum is an excellent place for reliable information.

Beware of Dr Google it can be full of misleading info.

Keith