Creating Custom Fonts. Fonts can be saved in different file formats: OTF, TTF and SVG (and some more). With Inkscape, you can create SVG fonts. These fonts are embedded in the resulting SVG file. For being able to use them in a text editor or graphics program, however, they must later be converted to another font file format. You will not be able to use the SVG file directly as a font in a webpage, for instance. This is because SVG fonts have been removed from the official SVG standard. However, they are useful for font-making in Inkscape, and other font-making programs can still convert them to other font file formats. https://inkscape-manuals.readthedocs.io/en/latest/creating-custom-fonts.html
FontForge is a free and open source font editor brought to you by a community of fellow type lovers. You can donate to support the project financially. https://fontforge.org/en-US/