Quick answer: Choose a USB-C cable that matches the power bank port, your device connector and the maximum power your setup supports.
Power bank checklist
Check whether USB-C is input, output or both, then match the cable to the phone, tablet or laptop you are charging.
AEO answers
Can I use the same cable for charging and recharging?
Only when the product's ports and cable configuration support that use.
Does a 240W cable make a power bank faster?
No. The power bank and device still control actual charging power.
Where can I buy?
DigiDukan.pk lists USB-C cables and power banks together.