you can buy some gear and go bandos there is guides on youtube, you can do barrows runs, and grifolic and ganodermic creatures aswell, i would recommend merchantinting aswell for easy money u can get without much work.
If you have/are willing to get 85 dungeoneering, then frost dragons is a good option. With average gear, you can make about 1M per hour. The downside to doing frosts is that a lot of worlds are filled with bots so it might take a little bit of time before you can find a decent world.
I doubt anyone is going to give you any direct items to merch because generally speaking the more people trying to merch something the less of a profit margin you have to work with. What you wanna do is try alot off commonly used items for combat such as whips, barrows gear, nex gear, polypore dung stuff ect ect. You buy the item at 5-10% more and see what it buys at , then you sell that item at -5-10% (sometimes MORE) and see what it sells at instantly. Then you try to buy some at the low rate you SOLD yours at then sell them for what you BOUGHT your initial purchase at. With the newest ge limitations most "flipping" is dead, so it may take some time to find a good enough item with a high profit margin with the new constraints.. when you do find some items its just doing a ge run a couple times a day to make money.