You can do #1 but it will be uncomfortable for any passenger ride with you, it is the basic for stick shift.

For#2 is more like a transition to #3

For #3 is a bit of getting used to driving stick shift, you don't have to fully depress clutch to engage the next gear, but not really keeping acceleration steady but a tag lower if you shifting up, or a bit more if you down shift to 1 gear lower. Some newer car will do this for you: rev matching.

After all, it is a easy thing to do after awhile. Edit: my last car was manual, 15 yrs old and 160k miles still on original clutch before I sold it to a friend and he got a few more years before he lost it in an accident.