Do consumer purchase product because of advertising?

No the purchase is done to accomplish a specific need, but when advertising comes to create a need it will be the reason behind purchase.

If the advertising campaign's messages and approach is effective, and the channels of communicating the campaign are relevant to the target audience, yes, the campaign will lead to sales. This is why testing advertising campaigns is critical in ensuring the effectiveness of the campaign before proceeding with production and media buy. Something which companies in this region shy away from spending money on, but Data on ROI proves testing campaigns is worth the spending.

Advertising can be influence to purchase but to purchase another things such as price , quality , place , are important too ,