First of all:
After completing Tutorial Island, you go to the Lumbridge graveyard. Make sure you still have the Shrimp and Bread you’ve got from the Tutorial Island in your inventory. Speak to Count Check, and ask him where you can learn more. He will teleport you one time straight to the entry of the Stronghold security where you can claim 10K. But to claim your rewards, you’ll need to activate 2 factor authentication of your RuneScape account. To quickly set that up, you can go into the account manage tab and click view inbox which takes you to your account setting where you set up your Google Authenticator in a few minutes.
The first level is completely safe, and no monster will attack you. But the second and the third levels have some higher level monsters. As a new player with 10 hitpoints and low food, I suggest you leave the stronghold after you loot the chest on floor 3.With the gold you get, you can buy some good gear and weapons and get into training. At a low level, killing Cows is a great way to train and make some money at the same time. The three drops from Cows combined can make a total loot of 250 gp.
Imps are also a decent money maker due to their Bead drops and the Mind talismans. There are a few Imps can be found at the Karamja volcano, and it is recommended to use Magic or Ranged since they teleport around quite a bit.
The goal with the F2P shop selling is to buy items in bulk and take them to a specialty store, and since specialty stores usually buy items for more than the high alch value, you can make a big profit. Across F2P, there is a lot of stores with a huge potential profit, and the key to finding good items is ones that are worth less than the high alch value and are under 200
You can buy cowhide from the Grand Exchange with your gp, or get it from killing Cows. As a F2P player, you can turn cowhide into leather and hard leather. Cowhides have a stable price of around 100 gp each, and by taking them to the tanner in Al Kharid, you can pay 1 or 3 gpto turn them into soft leather or hard leather. The Soft leather and the Hard leather have very similar prices, and the profit is 40 gp per tanned cowhide, so you can make +60K gp per hour!
You need a level of 15 smithing.
Upon reaching level 15 Smithing which you can easily get from doing Knight's Sword quest, you unlock Smelting Iron ore. By using a Ring of Forging, you guarantee an Iron bar outcome. The closest furnace to a bank in F2P is the Edgeville furnace which has no requirement. You can easily make +80K gp per hour!
You can also make Silver bars at level 20 Smithing. You can get 30 gp per bar and the total profit is +40K gp per hour!
Crafting is another low requirement skill that makes quite a lot of gp in F2P. Sapphire Ring is the most profitable jewellery to make in F2P, giving 110 gp per ring that you make, and this is 120K-150K per hour, depending on how focused you are.
At level 27 Crafting, you unlock Emerald Rings which is also a decent money making method, giving 80 gp per ring. This is +100K per hour, depending on how focused you are.
Tele-grab Nature Runes:
By taking a staff and a Law rune to this location in the Wilderness, you can telekinetic grab Nature runes for a big profit. Note that this is a popular PK area due to this money making method, but with the huge increase in the number of F2P worlds, this method isn’t so bad. Each telegrab gets 4 or 3 Nature runes as well as 43 Magic XP. By consistently telegrabing and hopping, you can get 200K-250K gp per hour!