How to convert URL to Base64 guru ampscript?

An external system generates the qr codes. On marketing cloud we have to retrieve the qr code, then url, after that i should encode it in base64 and show it as an image in a template.

this is the code i am using:

%%[
var @getRequest
set @getRequest = TreatAsContent(HTTPGet("https://api.qrserver.com/v1/create-qr-code/?size=300×300&data=https://sfmarketing.cloud/"))
set @enc = Base64Encode(@getRequest)
]%%
%%=v(@enc)=%%

from what I understand, it does not directly convert url to the correct base64 for me because if I try to do it in https://base64.guru/converter/encode/url