To get a reasonable gear range, particularly a suitable low gear, you will have to go to a much wider range cassette and your current rear derailleur may not handle the larger big cog. Also, what is your current drivetrain, 3xX? If X is 7 or 8, you may not find cassettes with a wide enough range and/or the interior gearing gaps may be unacceptable. Upgrading to 9 or more will require new shifters and maybe even a new freehub. There is more to 1X than just deleting chainrings.