The
TASCAM 8-Track Digital Portastudio 788, which has been discontinued, only has 6 TRS inputs ... however, 4 of those inputs can handle mic-level inputs, as long as you use the XLR adapters that supposedly come with the Portastudio. You can not record more than 8-tracks at a time.
If you plan to record your band, you would need another mixer to sub-mix your drums, then send one or two tracks of drums to the Tascam. The type of mixer you need for your drum sub-mix depends on how many channels you need, what kind of output you desire, and how big your budget is. I've always been a fan of Mackie because the mic-pres are decent for the price. There are so many different mixing boards available, you'll have to narrow it down based on your budget and the number of channels you want/need. If you can, get a board that will allow you to run 8 mics (XLR). This way you'll have enough for the future to mic all of your drums, including overhead mics for the cymbals.
I'm familar with the Tascam 788. Technology is ever changing, so I'm sure it is fine, although it won't meet today's standard of recorders, which is probably why it has been discontinued. It only handles 44.1 kHz, with a choice of 16-bit or 24-bit recording. This will work just fine, however many new devices go much further than this.
Tascam keeps an active
forum, which you might want to visit for questions specific to the TASCAM Portastudio 788.