You can pickpocket NPCs and steal many useful items from them. When NPC is suspicious, you risk being caught stealing.
How to do pickpocketing
To pickpocket, approach an NPC and hold down the "E" key. A wheel with question marks (❔) and blocked symbols will appear. To steal an item from the NPC, release the "E" key when the blue marker lands on a question mark (❔). Each time you attempt to steal something, your suspicion level will increase. The higher your suspicion level, the more likely you are to get caught. If you land the marker on a blocked symbol, you will be caught immediately. You will attain one wanted star if you get caught.
Goods
NPCs can have useless items with no value like: 1. Empty smoke pack. 2. Handkerchief. 3. Empty wallet
NPC can have various useful or valuable items like: 1. Snacks like Sprunk, Meteorite, P&Q, and Egochaser. 2. Smoke. 3. Pawn shop goods like diamonds, jewelry, electronic goods, and bonds. 4. Credit card. 5. Drugs like cocaine and weed. 6. Money. 7. Melee weapons like a Baseball bat, Knife, Machete, Switchblade, Golf club, Crowbar, etc. 8. Condom. 9. Metro ticket.
Note: You can use stolen credit cards at ATMs across the map to get money. Make sure to use the credit card quickly because it can get blocked.
Skill
When you reach 50, 100, and 500 pickpocketing skills, the marker to select goods will move slower and you will increase suspicion by less.
Thanks for reading!. You can also watch R3dfield's video about Pickpocketing on FiveM here.