Is MacBook Pro with two USB 3 ports equivalent of a USB A port?

It can be. USB-3 is a speed or performance designation. USB-A is a port type designation. USB 3 can be found on USB-A type ports and USB-C type ports.

On a 10 Year old MacBook Pro, it is a USB-A type port with USB-3.0 speed.

USB has more connector types than you can shake a stick at:

https://www.cablestogo.com/learning/connector-guides/usb

USB 3.0 signals can travel over any of these connectors:

• USB 3.0 A – which people often refer to as "USB-A", or sometimes, more ambiguously, as "USB 3.0"
• USB 3.0 B – a chunkier version of the USB 2.0 B connector on many printers
• USB 3.0 Micro B – often found on portable drives, and the "drive" side of the cables that come with them
• USB-C

Where do you need this information to take you?

Often the answers to isolated, narrow queries can lead you to not-quite-right conclusions.

What do you need to hook up, charge, network to, or support?