>>1530032bare minimium just get new tubes & tyres
& a chain
to change the chain you need a 'chain tool'
i suggest kmc brand for the chain. Any one for the right number of speeds the bike is.
remove the seatpost, grease it, and re-install.
you can just use a tub of wheel bearing grease from an autoparts store.
If the bearings like the headset or hubs of the wheel aren't smooth, i suggest you take them apart, clean, and repack with fresh grease. This will improve the bike a lot. If you don't do it, and ride it, you will destroy the bearings.
The tools required for each job are quite cheap.
It's just a headset spanner & large adjustable for the headset and a few cone spanners for the hubs.
you could also recable it. That would require new cables obviously, an awl, and a cable cutting tool. If there's friction in the cables it would be a good thing to do.
I'd also buy some nicer grips. I like Ourys.
Park tool, Sheldon Brown & Youtube in general have good guides for all this stuff. You can buy parts cheaply from wiggle or chainreaction, bike24 or bike-discount .de
