A betta and a 2 gallon bowl

Good day!

I've decided to attempt another try at keeping fish. In the past, I
was too young and quite uneducated for the task and the end result was
fish lasting no longer than a month. So since I have such a poor
record in the field of aquaria, I'd like to cautiously take a shot at
the popular betta first.

I'm planning for a basic setup and, for the time being, I'll probably
not go beyond 1 betta for awhile. But before I plunge into the abyss,
I'd be interested in receiving advice and suggestions from any
experts, hobbyists or housewives that have kept bettas.

With 1 betta, I will buy two 2 gallon drum bowls. One 2 gallon drum
bowl and a 5 1/2 gallon tank is also another option. The obvious
reason for more than one home is for easy cleaning and convenience for
the fish.

Now some questions... ;0}

a. Should I get the two 2 gallon drum bowls, or one 2 gallon drum bowl
and a 5 1/2 gallon tank? Since we're dealing with a betta, would there
be a significant difference between a 2 gallon drum bowl and a 5 1/2
gallon tank?
b. What would the water changes be like for a 2 gallon drum bowl and a
5 1/2 gallon tank? And how long would the water take to reach room
temperature with this bowl and this tank?
b. Is gravel a necessity?
c. Is a plant a necessity? Plastic or real?
d. Do I only need to dechlorinate the water or is there more to do?
e. When and what should I feed this betta?
f. Male or female? Can two females safely live together in a 2 gallon
drum bowl?

I hope these questions are not overwhelming. I truly want my future
betta to live a heathly and joyous life. I appreciate any responses.

Peace!