tablature for guitar and bass

For a guitar (accoustic or electric) you can use the guitar + tablature template in the new score wizard. It has already do what I'll explain for bass.

For bass, in the new score wizard, choose select instruments rather than a template. From the list of available instruments choose Electric Bass (or another appropriate instrument) and click the Add button. Select staff 1 under the instrument that will be created and click Add linked staff (it will become available when you click staff 1). To the right of staff 2 (which is created when you click Add linked staff) change the clef to one of the Tab 4 -str. options. This will add a linked staff when you click OK. Go through the rest of the New Score wizard, and when you add notes to one staff they will automatically be added to the other staff.

If you have a score with an existing instrument, press i and follow the instructions above starting with Select staff 1 to add a linked tablature to the instrument. The new score wizard will not run again so you wont need to reselect key and time and so forth.

For starters...
1) Open the MuseScore app
2) Choose template under 'Solo" - for guitar, use Guitar + Tablature
See:
https://musescore.org/en/handbook/3/create-new-score#choose-template
3) Enter notes onto staff.
See:
https://musescore.org/en/handbook/3/note-input#basic-note-entry

You can "import" sheet music via MusicXML
See:
https://musescore.org/en/handbook/3/file-formats#share-with-other-softw…

Import via pdf is experimental. Results may vary.
See:
https://musescore.com/import