API for checkout page not getting

[TrendsandTrades]

Hi Team,

We need API details for checkout cart. Please share link

[PayPal_Drew]

Hi @TrendsandTrades, 

Please check out our developer portal for API information. 

Thanks, 

Drew

[TrendsandTrades]

Hello,

Can i get more details where to get API and Details this is my website link and we have make in PHP custom code for this.

code is redirect to Paypal page but when i try to sign-in it show error check details can not do payment. 

can you help for this ?