You can register your account at https://stripe.com/en-my.
After that you can see your API keys at https://dashboard.stripe.com/apikeys.
Find Stripe Publishable Key and API Key on the page.
Go to https://orderla.my/admin/payment-gateways/stripe and enter those keys you obtain from Stripe's dashboard.
Click 'Update Change' after you enter the keys.
On form's edit mode, go to Payments tab. Tick the checkbox for 'Enable Stripe'. Then click 'Save'.