Affordable USB keyboards from reliable brand names plug into the computer's USB slot,
and are often automatically recognised by music making software.
Literally plug and play..

If not then you may need to look in settings and manually click to select the keyboard.

OR you may need to install a specific supplied driver [on disc or download from the manufacturer]
to connect the physical Keyboard to the music software.

These keyboards also usually come supplied with very useful free software bundles..

None of this should be dauntingly off putting...

We're here to answer questions if we can...