You can update the theme follow as Shopify guidelines. This link has detailed steps for you to upgrade the theme easily.
This is the link: Updating themes
Gumdrop
⌘K
- Getting started
- Sections
- Brand image
- Featured product
- Featured collection tabs
- Reveal text
- Comparison table
- Multirow
- Collection list
- Image banner
- Footer
- Header
- Announcement bar
- Gallery
- Testimonials
- Blog post
- Map
- Contact information
- Timeline
- Image showcase
- List cards
- Video
- Collapsible content
- Image with text
- Background video
- Icon box
- Blog post
- Blog post recipe
- Shop the look
- Image collage
- Curved text
- General settings
- How can I create my own custom product pages with sections?
- How can I create my own custom pages with sections?
- What is lazy loading?
- Fonts, colors
- How do I add product videos?
- How do I remove “powered by Shopify” from the footer?
- How do I set up swatches?
- How to enable social icons in the footer
- Image and video size recommendations
- Installing Shopify’s Product Reviews app
- Setting up navigation
- Settings overview
- Using the currency converter
- What version do I have?
- Why won’t my videos autoplay?
- Working with templates
- Advanced settings
- Home
- Gumdrop
- Advanced settings
- How do I update my theme?