Based on what I see from the screenshots there is a positive sign that Oauth handshake worked so now we need to determine why api calls did not.
The entry under Integrations in Magento 2 should show up as active. Could you click on Edit then scroll down to Integration Details and from the 4 values you see like below:

and try executing the curl command like below:
curl --location --request GET '[hostname]/index.php/rest/V1/categories' \
--header 'Authorization: Bearer [access token]'
Does that return a 200 JSON response?
If not then attempt it like below:
curl --location --request GET '[hostname]/rest/V1/categories' \
--header 'Authorization: Bearer [access token]'
If this works but the first call didn’t it means you need to add ReWrite Rules to your server like below:
RewriteRule ^index.php/rest/(.*)$ https://%{HTTP_HOST}/rest/$1 [L,R=301]
Hope this helps.