Lockdown Cycle Camping Trip Next Week (involving my Back Garden, because all the campsites are closed!)

Talk about "the title says it all"!

I have vacation time booked next week, and I was hoping to go cycle camping in the South Downs
(a hilly bit, in the South of England).

BUT

Well. you know, real-world stuff and all that.
All the campsites are shut by Government decree.

So I will just have to pretend:

1. load up my bike with camping stuff 
2. cycle about a bit
3. pitch my tent at the "simulated" campsite
4. cook up some food with the campstove I will have just cycled about with
5. sleep overnight in the tent.
6. repeat steps 1 - 5 as required.

OK, so the "simulated" campsite will be the (small) rear garden to our house.
I have a small tent, so that is OK
(basically, anything over 2.4m (about 8 feet) square is going to have problems in our garden, which is part grass, and part decking, with a step between the two! and try and avoid the two small sheds and the washing pole and the path, while you are there! Actually, the closer to 2m (about 6 feet 6 inches) square, the better).

For the "distance" the "campsite" is supposed to be away from our home, I am undecided whether to go for 20 miles (32km) or 50 miles (80km).
I am going to assume that I am about 5 miles (8km) from the nearest shops, so any rides to get groceries must be at least twice that length.
The nearest "natural" watersource (a canal) is a maybe a mile (1.6km) away, so I could use that if i want to boil my own water.

Restroom?
Hmm.
Let's assume the campsite has one (which means I can use the "house" toilet).
I have yet to decide if I can use the "house" taps/faucets or not.

I only get to camp with the stuff I lug about on the bike.
If I sleep in the house, that counts as a night in a "motel" near the "campsite"

Power/internet?
Let's just ignore the power issue, but the only internet I get while "away" is to write a "diary" blog on how I am getting on, and sharing it with some of my cycling buddies on Facebook.
No two-way interaction.
Just me posting.
No checking status and reading peoples' updates.

Guess I had better bring a book - a long one.
I had been meaning to re-read some Sholokhov (the 1965 Nobel winner), and this seems like the perfect chance!

p.s. "Cycling" mileage can either be real cycling, or "trainer" duration, based on a suitable conversion ratio - I am thinking 10 mph (16 kph) for a heart rate of 120, and 10 kph (6.1 mph) for a heart rate of 90 - so 20 miles is 2 hours at a heart rate of 120, or a bit over three hours just plodding along with a heart rate of 90. I suspect it might be easier to just cycle the mileage ;-)