Hi and welcome to the forum. I was in the same place a while back and am still learning a lot of how to do what and what is and isn't important, which varies from player to player.
You will get lots of great tips here. Some like to play a created sim, one of the townies, but for me, and it is just me, I feel as if I am in the movie Invasion of the Body Snatchers and I am one of the body snatchers.
I prefer to create my own sim (which you will see here mentioned as CAS), which can be fun, but also a bit (at least for me at first), overwhelming -- so many choices to make!
One of the things I learned to do, for me at least, was to pick a career that allowed me to have more control over what my sim did as I learned to play. That meant self-employment. With just the base game I chose the professional author. I didn't have to worry about my sim getting up in time for work, hunger, bladder, social and energy levels while getting ready for work. I could get her up when I wanted, stay up as late as I wanted, not feel trapped. I was able to send my sim to the bathroom as needed, have a meal when the hunger meter was just below halfway or when I choose. Same with the others, I try to not let them get too low, no more than turning yellow.
You can find free food in several places, in Sunset Valley (SV) there is the park and I think near the diner where you can always find free food, picnic baskets. At the park there are trees that have fruit, apples and limes and you can go to the lakes, at least one of them, has some wild veggies you can get. At some of the homes you can find fruits and veggies to use. Get several of them, especially the apples and have them in your inventory so when your sim gets low on the hunger meter you can just have him/her eat an apple until you can get a meal.
In RV you won't find any picnic baskets, at least I haven't ever, but lots of places to get free fruits and veggies from yards.
As for a home, there are several options; you can build as was suggested here, buy a cheap home, unfurnished, and slowly add and update the necessary items. The Guide has some good info on how to set up a new home, what is important. If you are planning to get free meals from around the town, you can ignore the fridge. Same with the shower, you can take a shower at the gym and not have to worry about it breaking down. Your bed is the most important, I think. You need a good one to have not just a good nights sleep, which affects your moodlets and thus the points you get, but also the amount of time your sim has to sleep. A better quality bed means less time sleeping and more time to work or play. Add what you want as you earn more money and can get better quality items. What you buy, add depends on your career -- author, medical, science have to have a computer. If not in those fields, you can ignore the computer and spend money on what is best for your career.
You can go to the library and read the skill books there, I think it is faster there than if you buy the books and read them at home. Plus it keeps your sim from going stir crazy, and can let your sim socialize as they chat with someone.
As for money, you can earn it as self-employed, or work a job and have an income. If you want to have some money at the beginning and don't mind cheating, there are two different ways to cheat and that is listed in the Guide under cheat tips. If you want just a little bit of help as you get started, go with kaching, as you can get only $1,000 simelons (I just think of them as dollars, buck, makes it easier) or go for the motherlode and get $50,000. Or don't cheat at all and earn it the hard way
Riverview (RV) is a free game you get when you buy the base game. I prefer it, but others don't like it, it is a matter what appeals to each individual. And each has pluses and minuses; SV has a nice park for sims to go and meet RV has none. The townies in SV are, in my opinion, either wacky or just mean. RV has more laid back townies, but can be less exciting in some area.
If you get interested in getting an expansion pack, or buy a store world, I would suggest reading about them here on the forum. You can learn a lot about them and have a better idea if you want to get one or not.
My suggestions to help in playing -- read the guide here and do some searchs when you have questions along with asking here. I have found a lot of help not only asking here but in doing searchs (but I love to do research, anyhow) which can lead to old threads that has plenty of info.
Have fun simming, and don't hesitate to ask questions, I have been here for over a year and I am still full of questions.
And one other tip, as you read here you will read things mentioned, of abilities, or objects that you don't have. It took me a while and some questions to realize that a lot of what is being mentioned are from expansion packs that I don't have. If you are not sure, then ask away.