Provided these ports are exposing separate DP channels from the processor, yes, two 4K 60Hz monitors can be supported.
Intel HD Graphics 630 supports three discrete DP 1.2 channels. Each channel supports a bandwidth of 17.28 Gbit/s. This bandwidth can be used to support one 2160p (4K) display operating at up to 60Hz, two 2160p displays each operating at up to 30Hz, one 1080p display operating at up to 144Hz, two 1080p displays each operating at up to 120Hz or three 1080p displays each operating at up to 60Hz. Note that connecting multiple displays to a single DP channel requires a MST Hub or displays supporting DP Daisy Chaining. Note also that, while up to nine displays could technically be supported across three DP1.2 channels from a bandwidth standpoint, Intel HD Graphics 630 supports a maximum of three monitors.
For more information on DP 1.2 capabilities, consult https://en.wikipedia.org/wiki/DisplayPort.
For more information on the Intel HD Graphics 630 solution in your processor, consult https://ark.intel.com/content/www/us/en/ark/search.html?_charset_=UTF-8&q=Intel+HD+Graphics+630 and then select your processor from the list.
Hope this helps,