Well first off if you search advanced here I can guarantee you will find all those answers and another tip, get a good book. It's worth spending $50 bucks on some decent info.
to briefly answer your Q's
good first snake:
- any of the antaresia, small, good handlers.
- woma, bit bigger generally around the 1.5 mark but it varies with the locales, great feeders (sometimes a bit too good but that's better than a bad feeder), nice temperament pretty IMO
- MUrray darling carpet python, slightly bigger than a woma (about 2m sometimes more), great handlers, good feeders generally, pretty IMO not unmanageable size IMO.
- I also think roughies are a good first snake, they have a great temperament, similar size to a woma but with a much bigger head and huge eyes.
I speak as a general stereotypical view on the species however each snake is individual and it cannot be guaranteed that a snake will behave exactly in this manner. Each snake varies and that's what makes them special and individual like us. And there is really no best first snake IMO some scrubbies might be complete sooks although I'm yet to meet one.
Feeding - as a hatchie, usually about once every 5-7 days however it depends what you're feeding. The bigger the food item the less often feeding will be necessary.
gradually increase food size to what you think appropriate for the size of the snake. When the snake gets older, feeding will be less regular as the snake isn't growing quite as much so it will be about once a fortnight or if bigger meals are fed every 3 weeks. There is however no exact amount of time. They will just grow quicker or faster depending on what MD how often you feed. But don't power feed.
Enclosure - generally for snakes, timber is recommended as it retains heat better than glass. Melamine would be the most common material as it's clean looking and cheap however if you buy one from a pet shop it's usually a ripoff. Better to make one yourself or get one off someone who makes them etc etc. glass sliding doors, vents etc etc. size of enclosure depends on the snake. When the snake is a baby use a click clack which is simply a plastic tub. Down waste money on a proper enclosure that the snake will grow out of soon. In the DIY section I think there is a great thread for click clacks. Antaresia can usually be kept in a 3ft long enclosure, womas will do fine in a 4ft unless you get a Sa woma which are bigger and then I'd recommend something a bit bigger. Find out if the snake you want is terrestrial or arboreal as this will be a factor in choosing the enclosure. Arboreal want more height but still some length and terrestrial really don't need much height at all. There are a bunch of threads and care sheets regarding snake species which will give you dimensions for enclosures for the snake you want.
Heating and lighting is often a personal preference. Some like globes others like radiators or heat emitters. Terrestrial snakes generally only need a heat cord or mat as they want more heat from the ground. Arboreal snakes might be better with globes or other overhead heating unless you put a shelf in with a heatcord on or something so they have a higher basking spot. You need a cool and warm end which are pretty standard temps for most species. Warm end low 30's cool end med/high 20's and generally a basking spot of 34ish but most snakes are forgiving and won't mind a few degrees fluctuation. Other keepers will stated different temps which are good too. If you decide you want a diamond however, try keep the temps slightly cooler than average snakes as they are more sensitive and prefer cooler temps.
other than that, just make sure it's shedding well, give it sometime in the sun outside SUPERVISED. Feed defrosted rodents or poultry whatever. Don't do it cheap. Invest the money as it will bring much more satisfaction. Get a good thermostat and thermometer/s, fresh water, clean cage every so often and spot clean regularly. Blah blah blah. It sounds complicated but it all falls into place and everyone here wants the best for you and your snake so we're all willing to help!
i said it would be brief didn't I? Haha oh well.
Most importantly do your research as it will result in years of enjoyment! Use multiple sources, talk to breeders etc etc.
hope this helped and enjoy your snake! Oh and pics are a must and make e enclosure nice tehe!
i forgot you need appropriately sized hides one on either end.
oh someone said this already ooops!