There are 2 routes worth exploring in your case - either a new amp that has USB connection to wire into your PC and record stuff to DAW softwate OR you can just buy an audio interface and use amp and gear simulators to record into DAW. Both options should give you plenty of options.
If you do not need to record you could get away with Trio+ kit that enables you to loop your rhythm section and I believe automatically generate a drums and/or bass over it to create more of a band experience. This you only need to plug into power socket and into your amp.
If you want to use different instruments then you either might need to connect each device into audio interface or directly via usb if it’s possible. Basically your question opens a can of worms 
I recommend threads as below: