Hi Anastasia, so you will receive a lot of well meaning responses from folks here, and some not at all. That's just the nature of a forum. But since you are new to filmmaking, let alone the use of a new camera that you have no idea what you need to get started, I suggest learning to crawl before you take your first steps. Obviously, you cannot use that camera without some basics, and I mean just some very basic stuff to use it. I also don't want you to spend a lot of money now. So here is what I will advise you to buy. They are enough to get you started and learning, in fact you can make beautiful pictures with it over time as you get yourself familiarize with the camera. I also made sure that you won't be spending a lot - around $350 for the basic things. I included links where you can order the items. If you take care of them, they will last but be aware this is a starter kit.
What you will need are the following:
(1) LENS:
Panasonic Lumix G Vario 45-150mm f/4-5.6 O.I.S. Lens - $148
https://www.bhphotovideo.com/c/product/ ... 150mm.html(2) MEDIA:
SanDisk 256GB Extreme PRO SDXC Memory Card - $69.00
https://www.bhphotovideo.com/c/product/ ... s=pi&pim=Y(3) Battery Grip for BMPCC 4K - $66.00
https://www.ebay.com/itm/Mcoplus-Vertic ... 85c45fbf03(4) Batteries
Amazon.com – Buy 6 Wasabi LP-E6 batteries with charger - $50
I am suggesting getting the knock off battery grip because it is very cheap and will give you enough hours (up to 3 hours) of recording time. You will need batteries so go buy 6 of the Wasabi LP-E6. The battery grip takes 3 batteries at a time so you should have plenty. Oh, buy the battery charger too. You can find these sold in packs and comes with the charger.
Optionally, I suggest getting a small LED light since the lens is not a fast lens. It will also be nice for lighting your shots and experimenting with lighting which is very important to learn as a filmmaker. I recommend this one. Now this will add more money but with the optional items, you're going to be under $600 (if you get the light and a basic microphone), which is still very reasonable. You can get them later if budget does not allow at the moment.
(5) Basic Light Source
Aputure MC LED Light - $90 (Optional)
https://www.bhphotovideo.com/c/product/ ... s=pi&pim=Y(6) Audio (Optional)
There are many kinds of microphones and external recorders. For starters, you really don't need it. But if you are going to want to have good audio, it's good to invest in one. You can get this later.
Once you have everything to get the camera working go use the camera whether it is taking some shots of sceneries outdoors or of people indoors - and just have fun with it first. Also, set your camera so you are recording in Prores 422 LT at 4K UHD, 24fps. This will give you better mileage on the SD card.
Without spending so much, you will be able to learn and if it doesn't work out, it's not a big hole in your pocket. I do hope you'll learn to love making pictures. Good Luck!