You need to paint the whole cupboard,startingfrom the bottom. Here starting is a/an -

You need to paint the whole cupboard, starting from the bottom. Here starting is a/an - Non-finite verb
A non-finite verb is a verb form that does not show tense.
Most non-finite verbs found in English are infinitives, participles and gerunds.
আলোচ্য বাক্যে, ‘starting’ verb টি কোনো tense নির্দেশ করেনা।
- এটা Present Participle এবং non-finite verb.