Axis and Allies 1941: Transport Rules for on loading and offloading units
Yes, what you are describing is possible and called an Amphibious Assault.

However, the sequence load -> move transport -> offload is not limited to situations in which you land in hostile territory, but is also true for offloading into friendly territory.

Here's all your transport options for one single turn:


Board a transport from an adjacent territory, leave the units onboard as cargo or offload into an adjacent territory (which is called bridging)
Board a transport and move the transport, leave the units onboard as cargo or offload them into an adjacent territory
Move a transport, then board it with land unit(s), then leave the units onboard as cargo or offload them into an adjacent territory
Move a transport one space, then board it with land unit(s), then move the transport another space, then leave the units onboard as cargo or offload them into an adjacent territory
Board a transport with one unit, move the transport, board with an additional unit (keeping the transport's capacity in mind), then leave them onboard as cargo or offload one or both units into an adjacent territory
Board a transport with one unit, move the transport one space, board with an additional unit, then move the transport another space and finally leave them onboard as cargo or offload one or both units into an adjacent territory


Do any of the above offloads into hostile territory and it is an Amphibious Assault, which requires you to offload all units on the transport (you cannot choose to offload none or only one). Keep in mind that Amphibious Assaults are conducted during the Combat Move Phase, while transports into friendly territory take place during the Non-Combat Move Phase.

Also, remember that a transport can only offload once per turn and cannot afterwards load, move or unload, again - which is also and especially true for the aforementioned bridging maneuver.

One mistake in what you are describing though: Loading or offloading does not count as ONE move, but as a unit's ENTIRE MOVEMENT. So, if it either boards or leaves a transport or both, a land unit cannot otherwise move during this turn. Therefore, a tank cannot move 1 space and then board a transport, or leave a transport and then still move a space.

All of this is explained in the Unit Profiles chapter of the Rulebook, in the section on Transports, p.28f.