The environmental impact of agriculture practices is very localised. Data based on US agriculture which includes irrigated deserts doesn't reflect the impacts in the UK.
Beef/ dairy and sheep farming use a lot of marginal land in the UK and enrich poor soils and encourage biodiversity and wildlife food chains. There's relatively little additional water used beyond the direct rainfall. Additional feeds tend to use non-human food grade waste. The land used tends to be unproductive for arable use, so wouldn't be sustainable for supporting a plant-based population.
Chicken and pork would be better to reduce than beef and lamb.
Have an interesting garden with layers of planting, pollenating flowers, a water source. Let wild flowers grow in the lawn.
Reduce, reuse, recycle in that priority order is the best way to manage consumption.
Avoid fashion. Sparingly, buy things you love that will last.
Give experiences rather than objects as treats/ gifts. Cut token gift giving.
Explore what's on your doorstep. I found it crazy in 2020 meeting people I knew that had never gone for a mile walk from home before and didn't realise the paths and cycleways within a mile from home as they're always busy off elsewhere and doing "big" days out.
Walk/ cycle/ scoot local errands if you're not in passing. Reduce journeys, and blend them together where practical.