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I have made a number of things from glass using either a propane torch or a bunsen burner. There is plenty of heat for the job. Use a nozzel that gives a large spread rather than a pinpoint flame. You can make a bunsen burner for a propane torch tank; however, it has been some years since I made one of those.

Use "Pyrex" or "Borosilicate glass" since it will resist cracking as it cools. You can protect the glass while it cools by coating it with carbon right after you work it. This can be accomplished by turning the oxygen almost off on the bunsen burner or by wrapping a cotton ball arounf the glass and allowing that to smolder and leave a carbon deposit. Be careful with this, lest you burn yourself.

You can fabricate tools to shape the glass from graphite rods, like those used in carbon-arc torches. You can find sources of graphite material on the web.

If you are planning to seal electrodes in the glass, use small diameter copper that you have oxidized with a quick exposure to a torch flame.

I have made vacuum tubes before. With a little practice, you will be able to shape glass in surprising ways. I've been thinking about making tubes once again; and, now I know how to draw a really hard vacuum. (Oil diffusion pump)