HI there,
Your theme has some very opinionated input styles, which makes it difficult to override, but this custom CSS will work:
form[id*=give-form] #give-donation-level-radio-list>li input[type=radio] {
display: inline-block !important;
}
Add that to the bottom of your theme’s styles.css file; or go to “Appearance > Customize > Custom CSS” and add it to the bottom of that setting. For more detailed info on adding custom CSS, see here: https://givewp.com/documentation/resources/handling-custom-css-in-wordpress/
Regarding the Offline Donations, it doesn’t appear as if you have Offline Donations enabled on your form at all. You’ll want to go to “Donations > Settings > Payment Gateways” and make sure OFfline Donations is enabled. Whether it’s on the Give Form page, or embedded via the shortcode it should not matter at all — if there’s a problem selecting the proper gateway (once it’s enabled) then most likely that is another theme issue, but you’ll need to enable it so I can see that problem live in order to provide additional custom CSS.
Review that and let me know how it goes.