If by "gas" you mean gasoline, for a glow engine the answer is "NO". Only use gas in engines set up for it.

Traditional glow engines use primarily methanol and oil (castor or synthetic equivalent - not petroleum oils.). Many run fine on just that. Nitromethane is added to help with consistency and idle. Some power increase, but that goes into a rabbit hole of debate, which is very engine and setup specific.
Common recommendation is a higher amount of oil for 4 strokes, and less for 2 strokes. But amounts vary widely depending on the engine manufacturer. And the debate goes on about whether the difference really makes a difference....
What ratio of ingredients to use depends a bit on the engine design, how it is set up (glow plug type, compression ratio via head shims) and ultimate use - general sport or all out max power, etc. Going without nitro may mean some tweaking of adding/removing head shims and changing to a different spec glow plug.
As noted above, common "standard" mixing ratios are easy to come by. So if you have access to the ingredients, is easy to do. Whether much cheaper or not depends on the sources you get them from, quality, and how big a batch you want to make..

Gasoline engines typically have a real spark plug, and use a gasoline/petroleum oil mix. The amount and type of oil is specified by the manufacturer.

There are a very few engines using a special glow plug that burn gasoline, and there are retrofit kits to convert a glow engine to spark and gasoline - but each has its own list of advantages/drawbacks as to how well they work, and haven't been widely used by most people.

Premade glow fuels can be bought via a local hobby shop, or on line. Cost is outrageous due to no more domestic manufacture of nitromethane (now from China) AND extremely high hazmat shipping fees.