I have a Mobile Intel® GM45 Express Chipset. Apparently it supports two simultaneous displays and it has two outputs (VGA and HDMI). But every scheme it shows has the laptop display in it, never two external displays at the same time (despite they had worked well one at a time).
No, you cannot do that. What operating system are you running? Windows 10? If so, your graphics are unsupported, and it is time to upgrade to a new(er) laptop.