Hello Juan
Remember that the TCP window size is a mechanism that operates at the Transport Layer while the Jumbo frame support feature operates at the Data Link layer. This means that there is no direct relationship between these two functionalities.
Also keep in mind that the TCP window size is not related to the size of individual segments, packets, or frames. The window size is the total number of bytes that can be sent before an acknowledgment is expected. This total number of bytes is typically sent in multiple segments, so the window size doesn’t have a direct relationship to the number of segments sent, or their size.
There is however an indirect relationship between the segment size and the size of a frame. This can be applied using what is known as the Maximum Segment Size or MSS which is negotiated at the beginning of a TCP communication, during the three-way handshake. More about the MSS can be found here:
The MSS is determined based on the maximum detected size of the underlying packet and frame sizes of the lower layers.
Now having said all of that, there is only one situation in which the window size affects the segment size: when the window size is set to something smaller than the MSS. In this case, it can limit the size of the segments that are sent, even if the MSS allows for larger segments.
By definition, it is not possible under any circumstances to have multiple segments encapsulated into a single IP packet or single frame. This is simply due to the nature of encapsulation. You can however do the opposite, that is, encapsulate a single segment into multiple IP packets, or a single IP packet into multiple frames. This is called fragmentation.
I hope this has been helpful!
Laz