You can use materials stored on your ship to synthesize (create) supplies, limpets, ammunition and other things such as repairs. Look in Panel #3>Inventory>Synthesis.
Dangerous advice for a new traveller as it could result in a stranded Commander, stuck beyond the natural jump range with insufficient materials to synthesize any more jumponeum.
I would instead suggest that you stop your current exploration and head along an establish path to a known endpoint.
Head back to the bubble, restock, review what you have learnt so far and make any changes to your ship that you think will help you.
Then, as a first trip outside the bubble, head to Colonia via the Colonia Highway (Google search to find the waypoint stations that you should jump between or follow some of the expeditions previously completed in EDSM)
Once at Colonia, then think about doing a dogleg onto Sagitarius A and the Station there to pick up the PS4 trophy.
It'll give you good experience of space travel whilst also keeping you close to the main routes where the Fuel Rats and Rock Rats can support you if you got into trouble.
As you head towards Colonia, you will learn a lot about what Space Wayfaring entails and whether it is right for you.
On the positive:
Lots to see, great sights to view
On the negative:
There is a high degree of repetition involved in Space travel, Space Madness is real
Other tips that I have learnt:
A good fuel scoop is arguably better than a good FSD - much better to get somewhere in one piece than to fly too close to a star and burn up.
Take an SRV with you for when you want a change of scenery from the cockpit. There is a certain release after spending a day jumping to land on a planet just have a drive around.